this is bbc news. i'm lukwesa burak. the headlines at seven: the us defends its decision to drop a huge bomb on islamic state militants in afghanistan — 36 militants are thought to have been killed. the us also confirms it's assessing its military response to north korea's nuclear programme — china warns conflict could break out at any moment. a huge operation is under way to move thousands of people from besieged towns in syria. the national union of teachers says it's prepared to take legal action against the government, over part of its plans to expand selective education in england. also in the next hour, remembering the kidnapped chibok girls. a vigil has been held in lagos to mark the three years since the mass abduction of more than 270 schoolgirls by boko haram extremists. and the online booking site air bnb improves its security after a bbc investigation finds scammers have been burgling homes.

good evening and welcome to bbc news. the us says a huge bomb — dropped on so—called islamic state militants in afghanistan — was "the right weapon against the right target". president trump authorised the use of the weapon — known as the mother of all bombs — for the attack in which 36 militants were killed. the commander of us forces in afghanistan generaljohn nicholson said it had been carried out in coordination with the government in kabul. the former afghan president hamid karzai has condemned the attack. here's our security correspondent frank gardner. a remote valley in a remote country.

11 tonnes of high explosive. on an isis tunnel complex in afghanistan. the blast was felt 30 miles away. the weapon used is called a massive ordnance airburst, also known as the mother of all bombs. this was its first time used in combat. this was the right weapon against the right target. we will continue to work shoulder to shoulder with our afghan comrades. to eliminate this threat to the afghan people, especially the people of this region, and indeed the people around the world. local villagers confirmed that isis fighters had set up bases in the mountains behind them, and said the bomb had hit its target. but the strike was condemned by both so—called islamic state and afghanistan's former president. how could the united states use afghanistan is a ground for experiments, for testing weapons of mass destruction?

president trump's targets now include three major problem areas for the us: afghanistan, syria and north korea. the massive weapon that the pentagon has used in afghanistan is intended to send a message to its enemies, that you're not safe underground. in syria, the trump administration will be hoping that last week's cruise missile strike would deter presdent assad from any further chemical attacks. but north korea is the biggest gamble. mr trump is hoping that sending his powerful naval armada offshore will deter any further nuclear tests. the question now, though, is, can he manage three global crises simultaneously? it's very possible that if these three scenarios come together, syria, afghanistan and north korea, it would overwhelm the policy—making capabilities of mr trump's administration.

it would overwhelm the strategic planning capabilities of the pentagon, and it would overwhelm the resource capabilities of the us military. but president trump and his entourage now feel they are on a roll, tackling head—on the foreign policy challenges that the previous administration was unable to resolve. there is now the risk that ramping up the rhetoric could lead america in more conflict, or that in the absence of any swift resolutions, mr trump may simply turn his back on foreign adventures and focus instead on domestic issues. frank gardner, bbc news. live to the white house and our correspondent gary o'donoghue. gary, it's been what 2a hours now. what's the reaction been like in the us itself? well there's been generally sort of welcome reaction i think from the national security establishment here for what donald

trump deed. he has shied away slightly of suggesting that he might have ordered the specific use of this specific weapon but despite what the military say i think people are seeing this as a sign of this kind of muscular foreign are seeing this as a sign of this kind of muscularforeign policy are seeing this as a sign of this kind of muscular foreign policy that we saw in syria last week, and again in afghanistan yesterday. the next big test yesterday is of course north korea and that will really come to a sort of point this weekend because there will be celebrations in north korea, they have a big day tomorrow. that often coincides with them showing some of their military strength, and there is potential they may even detonate another nuclear device, and nuclear test, their sect. he has promised to take action against north korea if the chinese don't stop them developing their need weapons and he has sent an aircraft carrier and other to say

that sell up and down the reimposed to prove he's serious. a higher risk there though, because he has engaged directly in afghanistan, syria. the risk ramps up with north korea because here we are talking about nuclear bombs. yes, hugely different situation in many ways. yes of course nuclear bombs. we don't know weather new north korea has a lethal weapon it can deliver, they have tested them but it is different from mounting them on missiles and sending them overseas. we do know of course is that north korea and a lot of its conventional military strength, artillery, etc, is embedded in the hills and mountains less than 40 miles away from the south korean capital and its 10 million inhabitants and the fear is that the us's strike would strike the south by accident will stop that

would be catastrophic in the capital, so eight very different risk, as you mention the new of it, but something the military bugle call the tyranny of proximity, you know, the potential damage that could be done with a pretty backward military and not a lot of resources, the north korean forces could do a lot of damage on that bonilla hashtag peninsula. we will find out how these stories are being covered in the papers later. the guestsjoining me tonight, helen croydon and the enemy —— independent business editor ms cox. north korea has vowed to mount a "merciless" response to any us provocation following comments from president donald trump that the isolated regime's nuclear weapons programme "will be dealt with."

meanwhile pyongyang is thought to be preparing for a massive military parade tomorrow at which its latest missile technology may be on display. 0ur reporterjohn sudworth is with a group of foreign journalists invited to witness the event, his movements are being monitored and tightly controlled. they sing in north korea, the spectre of war looms large over daily life. these girls are singing about being soldiers... while, not far away, real ones crowd into a shrine to the country's founding president, general kim il—sung. these are scenes akin to a religious pilgrimage, but of course, in honour of a still ruling family dynasty who have at their disposal all of the myth that would rival any of the world's great religions. and as the country prepares

to display its devotion at the anniversary of kim il—sung's birth this weekend, there's an awareness of the rising tension with america. translation: we should have the nuclear weapons. if we do not have nuclear weapons, the nuclear weapon of another country will fall on our soil. translation: it doesn't matter whether the americans make the situation on the korean peninsula tense. it doesn't matter. we feel safe because we have the great leader, kim jong—un. this week, the current ruler, kimjong—un, held this meeting where his late grandfather was honoured. he is also thought to be planning a massive military parade as a powerful tribute, and a message of defiance. children sing

this is a country where art and armaments are blended in singular purpose, to demonstrate to the watching world that its nuclear ambitions will not be stopped. john sudworth, bbc news, pyongyang. we're now going to speak to a counterterrorism analyst. he's in our washington studio. we have just been hearing that mr trump is setting himself up for three crises. syria, afghanistan, now, and everybody watching, north korea are watching very closely. what are your thoughts?” korea are watching very closely. what are your thoughts? i don't think we should necessarily focus on

president trump and this as his crisis where he is doing something. presidents usually are dealing with multiple crises, especially in the site a shredder kind of situations. president obama face the same situation and before him president bush but visiting the circumstances are different. the story is different but it is not buy a new president comes in and he creates any problem he faces a unique situation. so i think that's to say there are three crises that will constrain, that is not new, constraints a re constrain, that is not new, constraints are always there, and in fa ct i constraints are always there, and in fact i would say constraint are the most underappreciated of reality that most observers just miss, so i think when we say strategy or weather he will praise crises, i think we should separate it from the personality of the present —— president. what makes him think albeit ministration think that he can get it right where others have either stumbles, failed or

hesitated, or moved with caution? he is engaging directly here and there is engaging directly here and there is that huge threat that is making its way towards north korea customer it's a great show of arms. yes. look, i don't think anybody thinks necessarily, it's politically not the right thing to say, well, now begun going to be to succeed. busy physical leaders will say they will succeed that is public statement but in reality they do their best, and it isa in reality they do their best, and it is a very difficult situation. regarding north korea, one of the things that needs to be borne in mind here is that north koreans are not irrational. yes, they appear unpredictable and the idea that this isa regime unpredictable and the idea that this is a regime does not behave rationally i that is exactly the kind of view thatjohn yang —— that they want to send out and that they could have leveraged on the

negotiating table. let's talk about strategy. we are science —— seeing direct engagement by the us. does this get any idea in terms of a fixed strategy, though?” this get any idea in terms of a fixed strategy, though? i mean, there is never a fixed strategy, and ina there is never a fixed strategy, and in a situation where you are operating in different continents and you are operating in different circumstances you can't have a coherent strategy. you have two essentially tailor it, customise it to the situation on the ground so for example the united states is not interested in toppling esrd regime, and on this issue there is more of a meeting of minds between russia and the united states than air is generally at least admitted or known, but when there was a chemical weapons attack that forces the hand of the president to shift gears. why, because he can't be seen as the same or behaving in a manner that is similarto same or behaving in a manner that is similar to what president obama did

in 2013, in august, when he established a red line and then he said that he walked away from punitive measures against the regime. as kind of situations emerge, and you have to take a decision. it's not preplanned, i mean, there are times you had to do things you would otherwise not want to. what about is? they have now been directly attacked by the united states, will they be unnerved, that they are being targeted in such a direct way outside of iraq and syria? they have been targeted directly inside iraq and syria that matters more to crisis than any outpost around the world. i think that this changes much for the threat perception of isis, it's not as if they will now decide what to do. i think that isis, considering it isa do. i think that isis, considering it is a sophisticated entity and the threat it poses, because of sophistication, i mean, this is an organisation that is already

factoring in that they will lose leaders, whose facilities, it may not have expected that a moab would be use, but when they are out there they expect to be hit, this is part of their decision—making process. so i don't see how they will react differently, and what different options they have to counteract against such measures. thank you very much for your time. my pleasure. the national union of teachers says it's prepared to take legal action against the government, over plans which it believes are being used to expand selective education in england. the union has said it's identified schools which it believes are bending the rules by introducing some selection in comprehensive schools based on the results of a test. the move comes as ministers seek to lift the ban on new grammar schools. our education editor bra nwen jeffreys reports from the conference in cardiff. grammar schools have a long history. in altrincham, 100 years of tradition.

then, almost 20 years ago, new grammar schools were banned. now, some comprehensives offera grammarstream — for many, a way of stretching the brightest. but could this also be used to get around the law? so today, a warning of legal action. they fear ministers could encourage more of this. the schools where we'd have an issue around this is a school that's advertising a grammar stream, that is putting children through tests for it, and where we get the sense from documents and other things that children stay in that stream, that it's actually a selective system that is being introduced. that's what we would want to challenge. is this essentially a shot across the bow of the government, to say don't try to do this without changing the law? what we're saying to government is if you want grammar schools, you have to win it through the parliamentary process. do not try and go round the back way. who can tell me what soluble was? for schools like elton primary in cheshire, the big worry is budgets. bills going up mean less money

per pupil, leaving school governors facing tough decisions. we're already having to consider over the next three years losing at least two teachers, merging year groups, potentially shortening the school week by one or maybe half a day. these are all things that we are having to consider. for teachers, that means fears aboutjobs, so a warm welcome for labour's shadow chancellor. this is the first real terms cuts in school budgets for two decades. this is the worst school funding settlement, since, to be frank, i was wearing flares. settlement, since, to be frank, schools can stream pupils after they get a place. the government says that's perfectly legal. and only a change in the law could allow new selective schools. a young british woman who was stabbed to death on a tram

injerusalem has been named as hannah bladon. the woman in her early 20s was taken to hospital but died soon after. police say two other people were also injured during the attack. she was an exchange student from the university of birmingham. a 57—year—old palestinian man has been arrested. police say the suspect has recently been released from psychiatric hospital. a vigil has been held in lagos to mark the three years since the mass abduction of more than 270 schoolgirls by boko haram extremists. rallies have also been held to urge the government to increase efforts to free them. most of the girls, who were abducted from the town of chibok, are still missing. let's speak to isa sanusi from amnesty international, who joins us from the nigerian capital, abuja. thank you forjoining us. we understand many of the girls are

missing but do we have any more information in terms of their welfare or where they are? well, there is not any clear picture of what they are going through or what is happening to them but yesterday the government issued a statement saying that they are steel negotiating and they are making, doubling their efforts to ensure the girls are rescued from boko haram. we are talking about this now because it is the three—year anniversary. do you get the sense that the girls have slipped from public consciousness? well, i can say actually the momentum is going down. if you remember in the last two years there was a global movement, there was global advocacy, so movement, there was global advocacy, so many international personalities and celebrities were actually taking pa rt and celebrities were actually taking part for the rescue of the chibok

girls. but momentum is actually reducing, maybe because of the gains made in rescuing some of them but here in nigeria actually the momentum is still very high. people are still pushing, many advocacy groups, top politicians, civil society organisations are still asking the government to double effo rts asking the government to double efforts to ensure that the remaining 197 or 94 girls are rescued from boko haram. amnesty international puts together a report, i understand, which pointed out that the government had been warned the possible kidnapping. they also criticised the government for its slow response. how much have they done since that report because these kidnappings are nothing new in nigeria? yes stop at that time we actually issued a statement saying that the government received a

warning before the mass abduction of the over 200 chibok girls at the school. in fact, the over 200 chibok girls at the school. infact, every the over 200 chibok girls at the school. in fact, every day, almost every day we get stories from people of abductions, places are often u nsafe. of abductions, places are often unsafe. sorry, i want of abductions, places are often unsafe. sorry, iwant to of abductions, places are often unsafe. sorry, i want to get as much asi unsafe. sorry, i want to get as much as i can from you. what is that the government doing to help the situation? the government is ashley saying it is doing a lot and it is also saying that it is negotiating and some girls were rescued in october and actually the government is saying that look, we are doing our best, but advocacy groups and top personalities are saying that you have to do more because we are not convinced that what you are telling us. very quickly and finally

we understand that a lot of these girls are increasingly used as suicide bombers but also used to raise money. do families pay for their girls to be returned? well you know, most of these kind of deals actually, the details of a kind of details that come out in public but the most worrying thing is that the tendency of boko haram using these girls that they have abducted not only the chibok ‘s but others, forcing them into suicide bombing, turning them into sex slaves, and using the men among them as combat in theirfight using the men among them as combat in their fight against people and the government. that is actually the most worrying thing, they are using their abductions as a recruitment tool, in some cases, and because of the pressure ince security agencies they are feeling, they are blogging

more and more. 0k, they do very much for speaking to us from abuja. the evacuation has begun of as many as 30 thousand civilians from four besieged towns in syria. buses are taking people from rebel held areas west of damascus and from two government controlled towns. benjames reports from beirut in neighbouring lebanon. ready to move after a series of delays. ambulances and buses are taking civilians and fighters from besieged towns in syria. foua and kefraya are held by the government. madaya is an opposition town. another, zabadani, is also part of the deal. it's thought people there will begin to be moved as late as saturday. all four towns have been under siege for more than two years but many people didn't want to leave their homes. translation: they call us migrants from our land. we don't know what to say at this time. you feel like you're leaving your land, we are leaving our lives,

our hopes, ourfuture, our memory, our past. the un has described the humanitarian situation as catastrophic in these places. activists shared footage last year that appeared to show people eating grass and leaves from trees to survive. people from the government towns were taken to this opposition held area near aleppo ahead of their onward journey. critics say starvation is being used as a tactic to force deals like this and redraw the sectarian map of syria in the government's favour. president al—assad insists he sees the movement as temporary. it's expected 30,000 people will be moved in this latest deal, the largest of its kind so far. some breaking his coming to us here

via liverpool. the uk news agency are reporting that calvin mckenzie has been suspended from the paper, the sun, after he expressed wrong and unfunny views about the people of liverpool. these remarks were made by mr kelvin mackenzie, about the evident footballer punched in a liveable city centre bar in the early hours of monday. news uk, confirming that the sun, messed kelvin mackenzie has been suspended has been suspended from the paper after exposing wrong and unfunny views about the people of liverpool. labour has accused the government of "rewarding failure" — in response to new figures which suggest the government will have to pay millions of pounds more than planned to atos and capita, two private companies which assess people claiming disability benefits.

our political correspondent eleanor garnier is here. what went so wrong, eleanor? basically the government has found itself probably paying more than it expected to and that is because the companies, these two companies, are doing more work than predicted. we are talking about personal independence payments, introduced across on and better trained in scotla nd across on and better trained in scotland and wales four years ago and they are benefits for people of working age you have the —— disabilities, helping people to cope with the extra cost of their disabilities. they have proved controversial in the past and some said that these assessments are unfairand said that these assessments are unfair and have been insensitive. the government when it took the project out said it would spend £500 million to spend on these two companies that assessment by the news agency p a set it looks like it will spend around £700 million on these two contracts. the government says that this is because more

people are being assessed than first thought and also because some of the decisions are being appealed, and that means of is the more work to be done by the companies. as the reaction from the government, is it to labour criticism ? many reaction from the government, is it to labour criticism? many people will be saying that there is more money going to consultants but what about the people who were actually looking to get this benefit? where are we with those? not only those questions but also the question of if there's going to be £200 million extra needed to be paid to this company, where is that money going to be coming from? and people are going to be missing out somewhere else along the line? that's a question we haven't been able to get an answer to from the government today. they are saying that they need to these assessments effectively because that is the way to get the right money to the right people and also to make sure that this is cost—effective for the taxpayer, too. interestingly we heard from the former secretary of state for work and pensions, stephen crabb. he said today that actually in the past over the last ten years

the department has not been very good at carrying out these assessments, i.e., it hasn't got the estimates right, so more people are claiming than expected and that is why these contracts are costing more. labour has said that the whole system is not fit the purpose, the costs are spiralling out of control, and has criticised, as you said, the government for rewarding failure. thank you very much. the online accommodation booking company airbnb says it will improve its security, after a bbc investigation found that people's homes have been burgled by scammers using stolen accounts. they hijacked profiles with verified badges and changed some personal details to pull off the thefts. the company says it will now warn members if their profile information is changed. chris foxx reports. like millions of people, christian had let out his home on airbnb while he was out of town as a convenient way to make some extra money. he had done so for years without a problem. but on his birthday, his home was burgled. i got that horrible text message

saying somebody is in the flat and it's not me, because my account had been compromised. christian thought he had let out his home to a verified profile, somebody who had showed airbnb government identification and had positive reviews from previous bookings. but the account had been stolen. the attacker had changed the name, photograph and contact details on the profile, but kept airbnb's "verified" badge. and christian is not alone. the bbc has spoken to two other people who were robbed this way, and three others who had their accounts stolen. and airbnb's facebook page has dozens of comments from people who have had their accounts compromised. there are many ways attackers could have been hijacking airbnb accounts. they might simply have tricked people into handing over their passwords. but there are ways airbnb could have defended against this. we put our security concerns to airbnb. the company said: those changes include two—step verification when somebody logs

in from a new device, and text message alerts if somebody changes your profile information. but, for christian, the changes come too late. he says the whole experience has left him with a bad feeling, and he may not use airbnb again. chris foxx, bbc news. tomasz schafernaker has the weather. where has the summer gone? it is certainly pretty chilly and it will not warm up. there is some rain around. we have had some rain across northern parts of wales, anglesey, snowdonia and some of the rain will be moving through the midlands this evening. later on tonight, it tends to fizzle away. that weather front will have patchy rain left over. the

second half of the night is mostly dry across the uk with some clear spells across northern england, northern wales and scotland. tomorrow, not a bad day. chilly conditions for all of us, but in the sunshine, it feels just about ok. into easter sunday, easter day, more of the same. hello, i'm i'm lukwesa burak. this is bbc news. the headlines: the us defends its decision to drop a huge bomb on islamic state militants in afghanistan — 36 militants are thought to have been killed. the us also confirms it's assessing its military response to north korea's nuclear programme. china warns conflict could break out at any moment. the national union of teachers says it's prepared to take legal action against the government,

over part of its plans to expand selective education in england. several thousand people have been evacuated from four besieged towns in syria. they are the first of up to 30,000 people due to be moved. now on bbc news, it's time for click. this week, fighting crime before it happens. and keeping warm in the arctic. oh, my god! i said keeping warm... oh, forget it. we are now more surveilled than we have ever been.

cities are covered in cctv cameras. authorities are gathering data on its citizens. it would be all too easy to confuse the real world with a sci—fi dystopia. mr marks, my mandate of the district of columbia pre—crime division. i'm placing you under arrest for the future murder of sarah marks and donald dubin, that was due to take place today, april 22, at 0800 hrs and four minutes. no, i didn't do anything. in the movie minority report, the pre—crimes unit race to arrest would—be offenders before they have a chance to commit their crimes. now, they use psychics but it turns out, something similar is being attempted using big data. in chicago, where the violent crime rate has exploded, law enforcement has been forced to try out unconventional ideas to combat crime. authorities are attempting to combine various technologies in an effort to predict where and when violent crimes might occur. marc cieslak went to

chicago to find out more. violent crime in chicago has seen a dramatic increase. radio: a 15-year-old male, shot in the neck. both shots fired at her. shots were almost indiscriminate. shots fired. we need a wagon with a body bag also. the drug industry is what helps them fuel the violence, by being able to pay for their activity. in 2016, 726 murders were committed in the city, a 19—year high. that's more than the number of murders committed in new york and los angeles combined. chicago is a city most famously known as the windy city. more recently, it has earned a nickname that few residents are proud of, though. they are calling it chiraq. that's because gun crime is so extreme in some neighbourhoods, they are comparing them to war zones. the issue has received increasingly negative attention in the us,

with president trump tweeting, "if chicago doesn't fix the horrible carnage going on, i will send in the feds". but many believe that to fight crime in the city, first, the authorities must understand its causes. eddie bocanegra has for years worked to help young people surrounded by violence in the city. now a director of the ymca, he also serves on the mayor's commission for a safer chicago. good seeing you, sir. so this space here that you've got, what do you use this for? so we use this space for a lot of our kids, between the ages of 13 and 18. many of them who are in gangs. many of them who are on probation or parole. more importantly, kids who experience a lot of chronic violence. when you see the front page of a paper, saying a 15—year—old person killed someone else, these are the kids. gunshot victim.

the response from chicago's police department is a new initiative, driven by technology, which aims to predict where crimes are likely to occur. the university of chicago's urban labs are assisting the police in its efforts to integrate this technology into its operations. we have a lot of expertise in analysing crime patterns and trends in the city, from years of working with data on the city of chicago. and so we are leveraging that expertise to really help the police department think about where it should be allocating its resources to be most effective. so what kind of data or information is it that the police are providing you with here at the crime lab? we have a number of datasets that we work with from them, including data on crime patterns, actual crime incidents, arrests, victimisations.

a number of different methods of analysis are used, including machine learning and predictive analytics. this is software which takes large volumes of data and tries to identify trends and patterns. these trends can then help predict where a crime might occur next. this is a heat map of homicides in district 7. and we are looking at this year over year, from 2011 to 2016. and basically, what you see on the map is the darker the red, the more concentrated homicides were in a given area. what sort of factors are you finding are influencing crime in these particular neighbourhoods? yeah, so, most of the prediction that we're doing is space—based. so, yeah, it's locations that are nearby that are high—risk locations, like a 24—hour liquor store, a gas station, where people tend to congregate. the weather seems to be playing a very big role in the data. you know, we've just had a beautiful weekend and we just had significantly worse amount

of shootings than we had previous weekends. the police are using these predictive tools to inform the deployment of officers and resources to areas where they think crimes are likely to occur. neighbourhoods in chicago's west and south side are some of the city's most violent. it is these neighbourhoods which have been chosen to test the technology in a pilot scheme. we are just driving through chicago's south side now. now, this is one of the areas which has experienced the highest incidence of violent crime, mainly gun and drug related. to see how all of this different kit works, i'm on my way to a police station which acts as a command centre, bringing all of the technologies together. heading up the project is deputy chiefjonathan lewen of the chicago pd. so this is our strategic decision support center. so this is where you bring all of your different technologies together? it is.

this is the first time that this level of technology integration has been done, not only here, i think, but around the country. so what can we see on the screens we have got around us? so, all around us are various sensor inputs, cameras, gunshot detection. the screen behind you is something called hunch lab, which is a geographic prediction tool that brings a lot of data into a model to predict risk for future violence. so what you are seeing on these little boxes here are areas where the model is recommending that we deploy resources and implement strategies to fight some of the violence it is predicting. and then it is telling us that we should deploy resources, visit businesses, do foot patrol, various tactics. shot spotterjust very quickly triangulates possible gunshot events using acoustic sensors that are located throughout the district, and it shows the officer exactly where, accurate to within 25 yards, that gunshot event occurred. and you can actually play the audio of the gunshot event, which we'll do now. so here's an event with nine rounds fired. gunfire.

and in this case, you can see the location is actually the back yard of a house, so that's going to be very accurate. so this is the decision support system and this is where everything comes together in one place. it will soon be available in the hands of officers on smartphones. so in this case, we are looking at a 911 call of a robbery thatjust occurred at 7600 south marchfield. there are four cameras within a 300 foot radius of that call. here is the real—time video from those cameras. these guys here, these are possible suspects, or... these are people that might possibly be involved ? potentially. how do we know that this is identifying the right people? we find that they are very accurate. we find when we test and measure them, that the model's recommendations, because we can backdate it, we can look at a known outcome period and see how it performs. and we know that it's picking the right people because we know that it is accurate. but does it make mistakes? of course. that's where the people come in. but some of this technology is proving to be controversial, especially this. it's called the strategic subjects list. where hunch lab is concerned

with predicting crimes and locations, this list is concerned with predicting crimes and individual people. so this is a risk model. just like hunch lab is a place—based risk model, this is a person—based risk model that is looking at variables such as arrest activity, so have you been arrested for a gun offence in the past? have you yourself been shot? so it's using some crime victim data. is your trend line in criminal activity increasing or decreasing? what was your age at the time you were last arrested? it is using those variables. nothing about race, nothing about gender, nothing about ethnicity. it is using objective measures to determine risk for a specific person. it's basically telling us that this person is 500 times more likely than a member of the general population to be involved in a shooting, either as a victim or an offender. so in here, we can see his affiliations, his gang affiliations. he's a gang member. we can see also his, is this his arrest record that we can see here?

his arrest record. you can see that he has a weapons arrest. he was arrested here for aggravated battery. he strangled somebody. so here's a first—degree murder charge. here's another arrest, this is a narcotics arrest. so the score estimates how much more likely an individual is to be the victim or the perpetrator of a violent crime. the police use this score to inform what they call intervention strategies. this is not designed to be a punitive tool. this is used to drive what we call a custom notification process, which is literally a site visit to this subject, to say, "you've come to our attention for these reasons. we want to get you out of the cycle of violence. we can offer you the following social services". maybe it'sjob training. maybe if they have children at home, it would be childcare services. "but also, if you don't leave the cycle of violence and you keep committing crimes, you're going to be subject to enhanced criminal penalties", because you're a repeat gun offender, for example. and can you see why, if police officers go and visit somebody out of the blue, it might seem like they are being victimised, for instance?

everybody who has a risk score has committed a crime in the past. otherwise they wouldn't even be in the model. groups like the american civil liberties union, though, disagree. they aren't happy about the use of some of these technologies. the police showed us a database of people who have been involved in violent crime in the past, and an algorithm which suggests if and when they might again be involved in a violent crime. they pay that person a visit. what's wrong with that? the police show up with... oftentimes in large numbers, along with a number of social service providers. but what they won't say is what social services are offering. is itjust them or is it their entire family? what is the success rate once that occurs? the fact is, is that most of the people who are charged for... you know, if you take two people who are arrested for a simple drug possession, if one is white and one is african—american, the african—american is far more likely to be charged, maybe even convicted. we have seen that there has been, you know, in essence, a "once convicted, always guilty" sort of theme that

comes out of this list. while there might be disagreements about the use of this technology, everybody i spoke to had similar ideas about an ultimate solution to tackling violent crime in chicago. it's got to be every, everybody that's a stakeholder in this coming together to solve the problem. what is really needed across this city is a commitment to community— based policing. i think a lot of it has to do with preventing, with healing, and creating a space where individuals can civically engage back into the community. well, that was marc and this is marc. fascinating story, i have to say. how do you get on to that list? the police said that the list is composed from people that have committed violent crimes in the entire state of illinois. that is the prerequisite for getting on? they only consider people who have previously committed crimes?

yeah, if you've already committed a crime, especially a violent crime, you might end up on the strategic subjects list. well, interestingly, earlierthis week i spoke to dj patil. now, until recently, he was president obama's chief data scientist. i asked him about this and this is what he said. ihave... many, many deep concerns about the presence of these things. the fundamental one is the transparency of the algorithm. very recently in the us, we had a case that was written up by propublica. what was being used was a number of variables that were very prejudicial. and specifically, your race, your background, your life experience. you know, these datasets of offenders, we also know, have oftentimes have an increased bias because of the way police enforcement happens, or is it happening in one neighbourhood versus another neighbourhood? now, do i think there is merit in the use of this data? absolutely. the way we saw it, and one of the reasons why we created the white house data—drivenjustice initiative, is that we realised

that, hey, a huge amount of these people have other problems and we can help them. welcome to the week in tech. it was the week in which we learned that disney has filed a patent for humanoid soft—body robots. minecraft said it would allow content creators to sell their work online. and amazon promised to refund up to $70 million to parents whose children made in—app purchases without their consent. naughtyjohnny! it seems some hackers like waking up texans in the middle of the night. all 156 tornado warning sirens in dallas were turned on at once. sirens. officials haven't yet tracked down the person responsible for the midnight hoo—ha but say they were activated via radio or telephone signals. an oceangoing robotic snake has popped up in southampton. the eelume has cameras and sensors so it can perform maintenance work below the waves.

could the boys in blue be about to go green? behold, the ford police responder hybrid sedan. the eco—friendly car features anti—stab plates in the front seat. but hang on, it's slower than the petrol model it is replacing in the states. and finally this week, little green people in your living room. globacore has released hololens, a virtual reality homage to ‘90s classic lemmings. guide your green—haired friends to safety across your worldly goods. just don't expect a refund for either in—app or real—world purchases. the arctic circle. beautiful. wild. and unforgiving.

and for three days, home to four fundraising friends. they will traverse 100 kilometres over mountains and frozen lakes in temperatures as low as —30 celsius. what do you think? group leaderjames' daughter suffers from mitochondrial disease, and this trek is to raise money for a charity that helps children with the condition and their families. these guys are all senior tech geeks by day, so to help them on their quest, we've equipped them with some of the best bits of supercool tech. here we have all our technical equipment. some people think this is a lunchbox, but it's not. battery— powered heated socks. these are electric gloves. but which of these extreme weather gubbins will actually do the job in these punishing temperatures? suited, booted and sufficiently powered up, they head off into the wilderness. so it begins!

one of the most vital gadgets we're using is this satellite communications device. so it's going to send connor's wife, my wife, john's wife, tuka's girlfriend a text message to say everything's ok. we are using some hand warmers. that's going to keep some of our tech kit that we've got in here from freezing up, particularly a load of battery packs that we've got. we've armed ourselves with a whole load of different battery packs. this one here is the ravpower, and it's designed to be worn. here we have the zerolemon power bank. you can see it is really sturdy. it is a little bit heavy but then again, it packs 30,000 milliamps. i'm going to hide the nomad tile trackable battery pack from james, who you can see behind me. i'lljust place it here. aha. there you are. wow, maybe i should have hidden it better.

day one. sun setting. it's about 7pm. that is frozen honey. john's eating it. it's been a long day. tuka, i think we made it just in time, my friend. quite exhausting. we're all knackered but... very happy to be at this wilderness hut that we just got to. i'm trying out the heated insoles today. the insole has gone into the shoe. the cable comes out the back. we plug a battery pack into there. here we go again. we've got the gopro mounted to the skis. we're headed off in that direction, about 34k, i think, today. the little gopro hero5 session was left out overnight. i thought we'd killed it and i went

and kind of scraped the ice off it in the morning, pressed the button, boom, it's recording again. so it's like, ok, that's seriously cool. i've been wearing a finnish smart watch that's been tracking my activity. as well as tracking your location, dropping a breadcrumb of gps coordinates as you move, so once you've done something, it goes, "how was that? was it excellent? was it very good? was it average?" yeah. i'm going to say that was poor. i'm just going to save that up on the touchscreen. the biggest thing i've found was that it gives you so much encouragement, you know, when you're wrecked and you're about to die after 12 hours. the heated soles in the boot are working quite nicely, giving me a bit of ambient warmth. so here we have the blaze spark infrared lens. keen to capture the northern lights, connor's got a smartphone night—vision adapter. flip in the device. into the charging socket. you download a app called blaze spark. very simple to load, and once you connect the camera, the app automatically starts and your phone becomes

a magical infrared lens. ok, because we had to lug quite a lot of stuff across the arctic, there's some bits of kit we didn't take with us. it's the biolite campstove 2. it's got a fan inside it, so as you light the fire, it blows air through the bottom, causes it to really combust quickly. it's also got an integrated battery pack. and it actually converts heat into electricity and keeps the battery pack charged up. so this thing has got a usb slot and the phone is on charge. it's already 3% up. it's really, really, really cold. my feet are warm, on the plus side. this is a scientific test. this hand has got a heated glove on it. this hand doesn't. laughter. this one's really cold! this one isn't. that's actually nice. it's quite a lot of weight you're carrying and you can only charge them up from the mains, so if, like us, you're trekking out in the wilderness for a few days, they are not

going to see you through. would you pay $500 for the gloves? personally? no. the gloves or the socks, i'll take the gloves. invent a great glove, because that would, i'd buy them very, very quickly. filling our water bucket for boiling. we don't want to go and fall in there because that's a long way down. i reckon it's about —18, —20. sadly, connor didn't manage to capture the northern lights on his night—vision cam but he did take these beautiful pictures on his phone. about 30k to go. perfect conditions. my activity levels, even though i've been trekking for two days solidly, it only gives me 83 out of 100! laughter. thanks for that! it keeps you on your toes, knowing how much sleep you need. it tells you how much rem sleep you had, how much light sleep you had and how much deep

sleep you had. and it records, therefore, on the basis of that and the day's activities, the previous day's activities and efforts, how ready you are. when you know you've got that measurement happening all the time, it reminds you to look after yourself and that's the key bit. i've been wearing thermic heated insoles now for a couple of days. the cable coming out the back of the boot gave me horrendous blisters and rubbing. so i cut the cable off and just turned them into normal insoles. this is the snow lizard, fully waterproof, solar powered iphone7 pack. even though your phone is very precious and this one is to me, for sure, you can do that. laughter. connor and tuka have lost it. and they are diving around in the snow. we still have 21 kilometres to go on day three. oh, my god!

how are you doing, john? so far, the crew has been really jolly and talkative. for some reason, there seems to be a little less talking now and the guys are just pushing on. blistered and bloody—toed, we approach the finishing line. cheering. that was the hardest thing i've ever done. we did it. done it. a truly epic challenge. you don't do this to feel warm and comfortable and cosy, actually. you get out to do something like this to raise the money that we have been trying to raise for the lilly foundation but also, to test ourselves a bit. and tech can take you so far, but ultimately, it's your brain and your endurance and so on that can take you all the way. but i would still like some heated gloves. wow, what a great bunch of guys

and what a great story, too, especially considering they filmed that all themselves. the good news is that so far, they've raised over £17,000 for the lilly foundation and we wish them and james' daughter, poppy, all the best. for more information on their story and everything else you've seen in this week's programme, check out twitter. we live at bbc click. thanks for watching. we'll see you soon. it is certainly pretty chilly out there and the weather will not warm up there and the weather will not warm up in there and the weather will not warm upina there and the weather will not warm up in a hurry. certainly not even

into next week. as far as the weather goes, sunny spells, some rain around us well. in the last few hours we have had some rain across northern parts of wales. heavy rain around anglesey, snowdonia and some of that rain will be moving through the midlands this evening. later on in the night it tends to fizzle away. we will have patchy rain left over. the second half of the night is mostly dry across the uk with clear spells across northern england, northern ireland and scotla nd england, northern ireland and scotland and a touch of grass frost outside of town. tomorrow, not a bad day. it will be fairly bright. the winds are still coming generally speaking out of the north. chilly conditions for all of us but in the sunshine it feels just about ok. into easter sunday, is today, again, more of the same. this is bbc news. i'm lukwesa burak. the headlines at eight. the us defends its decision to drop a huge bomb on islamic state militants in afghanistan —

36 militants are thought to have been killed. the us also confirms it's assessing its military response to north korea's nuclear programme — china warns conflict could break out at any moment. the international development secretary, priti patel, has accused government and rebel forces in south sudan of deliberately blocking food aid. a huge operation is under way to move thousands of people from besieged towns in syria. also in the next hour, a warning over schools. the national union of teachers says it's prepared to take legal action against the government, over part of its plans to expand selective education in england. and at 8:30pm, we'll be looking at how the city of hull is being transformed by a year—long festival of arts and culture.