tonight at ten, rescue workers in mexico are searching for survivors of an earthquake that's killed at least 200 people. almost half the confirmed deaths were in the densely—populated capital, mexico city, where many buildings have collapsed, and power lines have been cut. the powerful quake, which measured 7.1 magnitude, struck yesterday afternoon. many people are still missing. rescue efforts are still going on in the rubble of a primary school where 21 children have already been found dead. translation: i'm desperate. i want them to get the children out. i want to see something. we'll have the latest from mexico city and we'll be looking at the country's vulnerability to major earthquakes. also tonight... mark sampson has been sacked as manager of england's women's football team following claims of inappropriate behaviour in a previousjob. the second major hurricane to hit the caribbean this month has damaged the us territory of puerto rico. the latest advances in dna

research which could lead to improvements in ivf treatment. and a look at the art of graffiti before banksy, with a first major exhibition of the works of basquiat at london's barbican. and coming up in sportsday on bbc news we'll hear from chris froome, who won a bronze medal in the time trial at the cycling world championships in norway. good evening. in central mexico teams of rescue workers are searching for survivors after a powerful earthquake that's claimed at least 200 lives. dozens of buildings have collapsed, including a primary school where 21 children are known to have died and many others are still missing.

almost half of the deaths were in the densely—populated capital, mexico city, where power lines and gas pipes have been cut. the magnitude of the earthquake was measured at 7.1 and the epicentre was around 75 miles south of the capital. our correspondent aleem maqool is in mexico city tonight, where the rescue work is continuing. it is today the full scale of the destruction in the exeter city has been revealed. more buildings weakened by the frightening force of the earthquake collapsed overnight. and this isjust the earthquake collapsed overnight. and this is just one of the terrifying drama is playing out here. children trapped under rubble, confused and scared, but first one gets pulled out and then the other. they were among the young pupils trapped when their primary school

collapsed, it happened at lunchtime moments after the earthquake struck. at least 20 children are known to have been killed here, many more are missing. this school has become the grim symbol of mexico's loss. translation: i am desperate, iwant them to get the children out, i want to see something. this is my building. this is the moment the earthquake hit yesterday. those who escaped felt lucky to be alive. earthquake hit yesterday. those who escaped felt lucky to be alivelj was escaped felt lucky to be alive.|j was inside the building and it collapsed. everything came around. cctv footage from a shopping centre showed the roof starting to collapse. this woman getting out of the way just collapse. this woman getting out of the wayjust in time. on their mobile phones, people captive count was shocking videos of buildings collapsing. —— people captured

counting videos. many who survived wandered around in shock. it is extraordinary that even though much of mexico city appears to be ok you can turna of mexico city appears to be ok you can turn a corner and find something like this, a building that used to be apartments or an office block but where it has now been reduced to rocks and dust and where people lost their lives. also, all over the town, lines of volunteers, people trying to help those who may still be alive. as we spoke to the rescue workers began to raise their hands to ask for a few moments silence to try to hear any cries for help. but nojoy this time. try to hear any cries for help. but no joy this time. people all over this city and beyond in the rural areas affected are joining to focus their energies on saving any life they can. translation: we are

organising with the volunteers we have doctors and nurses, and working with our own materials and supplies from the people. we need antibiotics, healing patches, wooden boards and ropes, blankets and food and medical help. but some now sleep on the street, afraid to be inside, traumatised by the violence of the quake. there may be a spirit of togetherness here now but there is also an acute sense of loss and fear. we are very close to that school and i'm having to whisper because even though we are a couple of blocks away we are being asked again to keep quiet in case there are any cries from people trapped inside the school, we know about 20 children are still missing and their families are still missing and their families are having an agonising wait. we have heard in the last hour or so that one girl has been found alive, they are managing to give her water

and food. but at the moment they are still trying to rescue her. they are silent now so they can hear the cries of any others. sadly any others pulled out of the rubble to date have been children who passed away. there have been good news story in other parts of mexico city, 26 people rescued from a building in an areai 26 people rescued from a building in an area i reported from earlier but for the moment, the focus is on rescuing those who are still unaccounted for and there are many, but there is also some anger as well because this is an earthquake prone zone and there are questions about why particularly schools are not earthquake proof. thank you for the latest. we will stay with this story and pick up on that theme he mentioned. mexico is located at the heart of an earthquake zone and it's suffered no fewer than 19 major earthquakes in the past century, including a devastating quake in 1985. so why is the country so prone to earthquakes and what have the authorities

there done to prepare people? 0ur science editor, david shukman, explains. the terrifying moment that the quake struck. this is a newsroom in mexico city, wrecked by the tremors. newsreel: the most violent earthquake in the memory of residents of central mexico. mexico is all too familiar with this kind of threat. these scenes were filmed in the 50s. and after every tragedy there has been an effort to make buildings tough enough to cope. this was an earthquake that struck in haphazard fashion... but in 1985 another devastating quake tore down 3000 buildings in mexico city, killing about 10,000 people. the government again ordered stricter controls on development and that did make a difference. when the tremors hit yesterday, this building was among many to shake but not fall,

using the latest designs to withstand the impact. sadly, dozens of other places were less resilient. the recent buildings in mexico city should have been built to withstand this kind of shaking. a magnitude seven earthquake, we were some way away from mexico city, and still buildings in mexico city collapsed. so what is behind this earthquake and why does it seem so severe? well, countries around the pacific lie on what is called the ring of fire, where the geology is highly active. so mexico has repeatedly suffered from quakes, caused yesterday by a violent shift in the rock. the cocos tectonic plate pushing into the north american plate. and if we look at a cross section, you can see how one of these plates is actually sliding under the other, moving at a speed of eight centimetres a year so the massive pressures build up and occasionally there is a sudden rupture. but making things even worse is that much of mexico city has been built

on land that is unusually soft, so any tremors from an earthquake are amplified. mexico city sits on this old lake bed. soft sediment with a lot of water in them. so when the earthquake strikes it, itjust goes like jelly and you get really high shaking. a lot of the buildings cannot handle it and theyjust collapse. so, long before this latest quake, the threat was very well—known and for years there has been the technology to keep buildings safe. the problem is making sure the rules apply everywhere and investigators will want to know what went wrong. were corners cut in construction, leading to such terrible losses? david shukman, bbc news. mark sampson has been sacked as manager of the england women's football team. the football association said his departure was connected to "inappropriate behaviour" during a previous coaching job in bristol. more recently he's been the subject of allegations of racism and bullying, allegations he's denied.

the fa's handling of the case has been criticsed by the sports minister tonight, who called it "a mess." 0ur sports editor, dan roan, has the story. from 6—0 to the sack in less than 2a hours. 0ne from 6—0 to the sack in less than 2a hours. one day after seeing his england team win in emphatic style, manager mark sampson finally lost hisjob this afternoon manager mark sampson finally lost his job this afternoon after weeks of controversy. the fa confirmed they had terminated his contract is due to safeguarding allegations made against him when he was coach at the bristol academy before taking the england job. the governing body said the full details of aids 2014 investigation into what they called inappropriate and unacceptable behaviour with female players only came to the attention last week —— details of an investigation in 2014. the issue was around his conduct and around the boundaries between a player and a coach. 0n reading that

report i felt what i saw was incompatible with the standard we would expect for somebody to work at the fa. the pressure had been building. former england striker eni aluko told me last month she had been bullied and discriminated against by sampson who denied the allegations and was cleared of wrongdoing in two separate investigations but speaking last night it was clear that recent events night it was clear that recent eve nts ha d night it was clear that recent events had taken their toll.m night it was clear that recent events had taken their toll. it was a difficult time but it is for eve ryo ne a difficult time but it is for everyone involved also it is a serious situation and everybody is aware of that. despite sacking him, the fa say sampson does not pose a safeguarding risk in the game. the government wants answers with the sports minister, tracey crouch saying... but was this just a convenient way for the fa to get rid of it under fire manager? i can understand why

people would say that but they are two very different things. the concerned that eni aluko raised were about perceived bullying and racism, this is a different issue. this is a spectacular fall from grace for a man who has transformed the fortunes of the lioness is leading them to two consecutive major tournament semifinals and guiding them last night to a winning start to their world cup qualifying campaign. the players showed their full support for the manager. that is the togetherness of the group and he is visibly moved. but behind the scenes sampson's career was unravelling and this evening his reputation lies in tatters. this controversy is now developing into a full—blown crisis for the fa and it is one they will struggle to escape from because next month a parliamentary select committee will summon senior fa executives to explain themselves and no doubt one question will be why the fa chief executive martin glenn knew about

that safeguarding investigation as long ago as november 2015 and yet did not ask to see the full report until last week when the fa were tipped off by whistle—blowers. also white was a debate sat on that information for all that time? there is no suggestion sampson broken any laws but what he did was sufficient enough for him to be put on a safeguarding behavioural development course and yet in that time he was the subject of two further investigations into serious allegations made by eni aluko. all this once again raises issues around the government and due diligence of the government and due diligence of the fa and the year after it sacked sam alla rdyce the fa and the year after it sacked sam allardyce the men's england manager afterjust one match, its recruitment policies, and as the sports minister herself said, what a mess. thank you. the island of puerto rico in the caribbean is without power after hurricane maria hit the us territory. the storm has weakened slightly, but there were wind speeds of 115mph as it moved across the island.

the us virgin island of st croix is also being hit. communications with the island of dominica, which was hit yesterday, remain largely cut off, but aerial photographs show flattened buildings and fallen trees. 0ur correspondent, will grant, is in puerto rico and sent this report. there is still no end in sight to this uncommonly powerful hurricane season in the atlantic. and the longer it goes on, the more records it seems to break. hurricane maria, now the strongest storm to make landfall in puerto rico in almost a century. when it hit, it certainly felt like it. maria struck the island with winds of up to 165 mph and dumped as much as 25 inches of rainfall in some areas along its path. that was on top of everything hurricane irma did here barely a week ago. the tiny island of dominica was directly in the path

of the storm and apparently suffered some of the worst of the damage. the country's prime minister described the situation as it was unfolding, calling the damage "mind—boggling." maria is slow—moving, creeping its way over puerto rico, meaning the window for potential damage and destruction lasted for many hours. the islands authorities had tried to prepare as best they could with thousands housed in evacuation shelters, others took refuge with friends and family. this is absolutely the worst hurricane experience i've had. we've lived in puerto rico for about the last 30 years, so we have experienced some. it was very loud, we heard a lot of glass breaking. we heard the waves or water hitting against the window. puerto ricans were relieved to have avoided the worst of hurricane irma, but it looks like they've not been so lucky this time around with hurricane maria.

many here fear the same kind of devastation seen elsewhere in the caribbean, all of this happening on an island that is, lest we forget, currently essentially bankrupt. manpower from the us emergency agency, fema, is on hand and millions in federal funds will be needed, particularly in the days to come. but most people in puerto rico can't get think about the clean up until they're sure it's safe to step out from their homes and shelters. 0nce maria eventually moves on, they can begin to assess the extent of the damage left in her wake. for many communities, though, maria has already finished off what are left behind. will grant, bbc news, puerto rico. at the united nations, theresa may has urged internet firms to "go further and faster" to stop the spread of terrorist material online. companies such as google, facebook and twitter have been

coming under increasing pressure to remove extremist material posted by groups including so—called islamic state. the prime minister talked of setting a deadline for material to be removed and the possible imposition of fines, as our security correspondent, gordon corera, reports. addressing the un general assembly this evening, a central part of theresa may's message was a challenge to technology companies. we need to go further and faster to reduce the time it takes to remove terrorist content online and to increase significantly their efforts to stop it being uploaded in the first place. this is a major step in reclaiming the internet from those who would use it to do us harm. as so—called islamic state suffers defeats on the physical battlefield, security officials know that it will increasingly turn to the virtual world to continue its campaign. seeking to radicalise, recruit and even instruct people on carrying out attacks all online. in this

campaign, the battle is far more evenly matched as the group makes use of technology built and run in the west. is posted 27,000 links to extremist content in the first five months of the year alone. 0n average, these links remained available for 36—hours and they were shared most in the first two hours. the uk ranks fifth in terms of countries where the links are most frequently accessed. to see how easy it is to find this kind of material, we carried out a simple test. after just a few minutes searching on popular social media sites, i have found propaganda videos and even instructions on how to trigger a homemade bomb. what the government wa nts homemade bomb. what the government wants is not just homemade bomb. what the government wants is notjust for the companies to ta ke wants is notjust for the companies to take this kind of material down an hourortwo to take this kind of material down an hour or two after it's reported to them, but for the companies to be more proactive and stop it being uploaded in the first place. politicians who havele looked into

this issue say they're frustrated that companies are not putting enough effort into this challenge. we know that these online giants are able to act swiftly when it comes to dealing with copyright. they are able to act swiftly when it comes to dealing with online child abuse. they need to put their huge expertise into dealing with terrorism. the companies say they are developing new tools, but say it's still not straight—forward, as one leading figure, meeting with the prime minister tonight, told the bbc. so i do think that we will get better at using technology to do this, but at the same time i really wa nt to this, but at the same time i really want to convey that a lot of this is contextual. if we had a rule where we said every time there is an is we would take it down we would remove a lot of journalist content. would take it down we would remove a lot ofjournalist content. we don't wa nt to lot ofjournalist content. we don't want to do that. the prime minister met with donald trump, security high

on the agenda. this evening she will sit down with senior figures from silicon valley calling on them to do more. gordon corera. bbc news. our new york correspondent, nick bryant, is at the un. apart from the challenge to the internet companies there was a challenge to the un itself? yeah. theresa may was echoing a lot of what donald trump said earlier in the week about the need for un reform. threatening financial penalties if it didn't happen. what she said was that there could be a 30% withdrawal of british funding. not for the un overall, but for some of the united nations agencies that britain thinks is under—performing. there are efficiency agencies, we know their names, unicef, the world food programme that won't be under threat. 0ther food programme that won't be under threat. other agencies, a development agency that the brits don't like. they run the risk of having their british funding withdrawn. among the other addresses

there today, let us talk about another notable one by the iranian president. what did you read into that? president rouhani absolutely slammed donald trump's speech yesterday. he said it was ugly, ignorant and beneath the dignity of the united nations. he also said it was a great pity that what he described as "rogue newcomers to world politician were threatening to destroy the iranian nuclear deal that was put in place in 2015 by barack 0bama." donald trump has said he's made up his mind about whether or not to withdraw america from that deal. he hasn't announced what it is. tonight he's coming under great diplomatic pressure to stay in, from the french, from the russians, from the french, from the russians, from the saudi arabians, iran's great regional rival. from britain as well, in that meeting with theresa may and donald trump, she reaffirmed britain's support for the iranian deal saying to donald trump, will you stay in. there is a fear as

president rouhani said today, that if that nuclear deal falls apart, then iran will accelerate its nuclear programme. nick, again, thanks. nick bryant there with the latest for us on the sessions there at the un, in new york. for the first time in the uk, scientists have succeeded in altering or editing the dna of human embryos. among the potential benefits could be improved ivf treatment and greater understanding of the causes of miscarriage. the research was carried out at the francis crick institute, in london, as our medical correspondent, fergus walsh, tells us. in this lab in central london, scientists are trying to unlock the mysteries of life — how one fertilised cell can go on to create a human. they're doing it by studying the dna of embryos in a dish in theirfirst week. this is basic research that's providing us with a foundation of knowledge about early human development within this first seven—day window,

and our hope is that this information can be used as a basis to build further understanding about underlying causes of infertility. inside the nucleus of our cells is our genome. made of dna, it's the instruction manual for life. the key sections are genes — 20,000 of them, which control how cells function. scientists at the crick institute were targeting a single, super gene called 0ct4 to see what would happen if it was switched off. now this is one of the donated human embryos they used, left over from ivf. you can see that the nucleus of the sperm and the egg haven't yet merged to share their dna. they injected the gene editing system, known as crispr, into each of them.

now, the crispr system scans the billions of letters of dna like a spell—check, until it gets to the 0ct4 gene and cuts both strands, removing a tiny section which inactivates or silences the gene. now we can see what effect that had. the healthy control, on the left, shows how an embryo should develop over five days, it's getting bigger and eventually developing a cavity at the centre. now compare that to the gene—edited embryo, it keeps collapsing, confirmation thatjust one tiny section of dna is crucial for healthy development. in the long term, it could help explain why women, like natasha, keep losing their pregnancies. last year alone she had four miscarriages. it's the unknown. we don't know exactly what's going on and to be able to research and find out the crux of what it is, what potentially it could be, could just save a lot of heartache. this research, in the journal nature, was not

about creating babies. but in theory, embryo gene editing could one day be used to get rid of inherited disease. that would raise major ethical issues. the aim of this study was basic research, it was to produce knowledge about human development. the embryos that were used in the study were never intended to be implanted. so we should, with respect to this study, put all talk of designer babies off the table. the crick institute in london is a world leader in gene editing, a technology which has the potential to transform medicine and our understanding of human biology. fergus walsh, bbc news. another two men have been arrested in newport, in south wales, in connection with last week's attempted bomb attack on a london tube train. the men, aged 48 and 30, were arrested under the terrorism act and it follows an arrest of another man in newport yesterday.

police say searches at four premises in newport could take days to complete. next week's referendum in iraq on the demands of ethnic kurds for independence is a "destabilising" exercise, according to the white house. the kurds who live in oil—rich northern iraq — coloured in red on this map — account for nearly a fifth of the country's population. for the past few years, they've been in the front line of the battle against the islamic state group. but there are growing fears internationally that if the territory did breakaway, it could cause renewed conflict in iraq. 0ur correspondent, 0rla guerin, sent this report. a bird's eye view of a country in waiting, at least according to the kurds. they have struggled for a state since 0ttoman days. here in northern iraq they have autonomy, but they are pushing forward with an independence vote which could redraw the map of the middle east.

his family told me they have paid in blood for their freedom and the international opposition won't stop them. translation: for the past 100 years they have been telling us, it's not they have been telling us, it's not the right time. if we don't move forward they will be telling us that forward they will be telling us that for the next 100 years. the nation is united. there won't be a better time than now. but there are possible flashpoints, like the oil—rich city of kirkuk. as the vote approaches, you can sense the tension. the city is multi ethnic, it's controlled by the kurds, but also claimed by the government in baghdad. arab leaders in kirkuk say

their community won't accept the referendum results and is increasingly fearful. translation: a lot of people are taking their valables away for safe keeping, whether it's expensive cars or large sums of cash. everyone wa nts to or large sums of cash. everyone wants to protect themselves. people have started to stockpile food. they are very afraid of what is coming. but at the pressure merger front—line they are poised for victory after their long battle for freedom. veterans here fought the iraqis in the past and lately the so—called islamic state. iraqis in the past and lately the so-called islamic state. this area was under control of isis. commander kemal kirkuki said they are in position a mile away. he said the kurds will remain foe kissed on the enemy. we make a decision to

continue fighting against isis until they will be finished in the area because they are not only danger for us, they are danger for all the world. they are a danger for democracy. so the referendum will not interfere with the fight against isis? sure, 10096, not interfere with the fight against isis? sure, 100%, no. not interfere with the fight against isis? sure, 10096, no. but the kurds may soon be moving into unknown territory. iraq's neighbours, who have their own kurdish minorities, are looking on anxiously. there is uncertainty here and in the international community about what will follow the referendum. kurdish commanders tell us they want to move peacefully to independence, they don't want trouble with baghdad or with the neighbouring states, but they say if conflict should come, they say if conflict should come, they are ready to fight. at the final rallies the promises of better days to come after what the kurds are calling their brexit. but if the

referendum goes ahead as planned, a new state could be born into conflict. 0rla guerin, bbc news, northern iraq. before banksy there was basquiat, a graffiti artist who became a sensation in the art world. jean—michel basquiat died of a suspected drugs overdose in new york at the age of 27, back in 1988. but earlier this year one of his paintings sold for £85 million and now the first large—scale exhibition of his works is going on show at the barbican, in london. 0ur arts editor, will gompertz, had a look.