this is bbc news, i'm lewis vaughanjones with the latest headlines for viewers in the uk and around the world. a police officer dies after being rammed by a car outside the us capitol building in washington — another officer is being treated in hospital. the suspect who emerged from the car with a knife and ran at officers was shot and died in hospital. the top homicide investigator for the us city of minneapolis gives evidence on day five of the trial into the alleged murder of george floyd. remaining calm under the pressure — the life—saving operation that took place while a fire was raging. and a different big bang — new research suggests the asteroid that killed off the dinosaurs may have helped create the rainforests.

hello and welcome. in the us, a police officer has died and another is in hospital after an attack on the us capitol. a man carrying a knife rammed a car into a barricade, before he was shot by police. president biden said he was heartbroken over the death of the officer. it's the second time the capitol has been targeted this year, after supporters of donald trump stormed the building in january. here's our north america editorjon sopel. sirens wail. we've been here before. lunchtime on a cold easter day and another emergency at the capitol. sirens wail. a man in a blue car rams two us

capitol police officers near a barrier. as he gets out of his vehicle, knife in hand, he's shot and has now died. immediately, congress goes into lockdown. a helicopter�*s summoned and lands in front of the capitol building. and the national guard, which has been on duty since the capitol riots ofjanuary 6, is mobilised. another terrifying moment for those who work in the congressional offices. at a hastily organised news conference, confirmation that one of the police officers has died as well. and it is with a very, very heavy heart that i announce one of our officers has succumbed to his injuries. but the assailant doesn't seem to have been on anyone�*s radar screens, and police are saying there doesn't seem to be an ongoing threat. it does not appear that he is known to the capitol police or the metropolitan police department at this time. crosstalk. sir? is this a terrorism—related

incident? _ it does not appear to be terrorism—related, but obviously, we'll continue to investigate to see if there's some type of nexus along those lines. it was only a few days ago that some of the intense security around the capitol, following january's shocking assault, was eased. just a week ago, the driver wouldn't have been able to get as close to the building as he did. what's happened today may be totally unrelated to the events of january 6, but there's a terrible sense of deja vu, a further heightening of the feeling of vulnerability. and once again, above america's august and imposing capitol building, flags have been ordered to fly at half—staff. barbara plett usher, our us state department correspondent is outside the us capitol. over the past weeks, i think the city had begun to relax a bit more because since january 6, there'd been a massive

security increase around the capitol building, as you know. there had been some warnings about possible attacks, but nothing had happened. and now something has, so people are on edge again and nervous about what to expect. now, this is nothing like on the scale, of course, of what happened onjanuary 6 — which was a mob storming the capitol building with arms, hunting down congresspeople, attacking police officers. this is — seems to be a one—man attack. at this point, it appears that he acted alone. it's also not at all clear that he might be, you know, connected to some kind of political or other cause. the officers who spoke to us earlier said that they were not calling it a terrorist attack and this man has not appeared on law enforcement radar before, he's not known to police, so it's not clear what his motivation was. that will obviously be a big part of the investigation but,

yes, it has rattled people to come three months afterjanuary 6, and some of the congressional aides that the bbc spoke to said that did make them nervous, especially with the security around, that another attack could happen. well, earlier i spoke to former fbi special agent thomas o'connor, who for over two decades worked on thejoint terrorism task force in the washington field office. we began by discussing how this latest incident highlights the dangers faced by officers in the us capitol. it certainly does, and it shows that the threat continues, whatever that threat may be from, and as your correspondent said, that is something that the joint terrorism task force which includes the us capitol police, the metropolitan police and the fbi, will be delving into and scrubbing all social media, and anything related to the subject who was killed on the scene today after this attack.

it may turn out that there is an ideological backing to this. it may turn out that mental illness with a combination of that is what led to this incident. the us capitol, much like westminster in the uk, is a target, and the officers who work at the us capitol every day put their lives on the line to protect their building and the people who are in it and they should be complemented for thejob they did. this was not a breach of security, this is what the security does. it stopped the vehicle from getting in, and those officers did theirjob and sadly one was killed and one was injured. you touched on the possible search now for motives which is clearly in the minds of so many people. what kind of areas will people be looking at, the investigating officers there? is it something like what we can all see, looking at social media feeds— what are the other avenues they will be exploring?

it is, social media in this day and age really does shine a light into the mindset of the person that is being investigated, but along with that there'll be search warrants that are served at this person's residence, the vehicle is being searched, all of these things come together, and there may be some fringe ideology, there is being reported a follower of the nation of islam which is anti—semitic, more of a racially—motivated group, but that doesn't particularly have to be the reason the person did it, it could be mental illness that was spurred on by conspiracy theories and ideological followings, but the mental illness is what pushed them over the edge.

staying in the us, a minneapolis homicide investigator has said police officer derek chauvin used "totally unnecessary" deadly force when kneeling on george floyd's neck during an arrest last may. he was giving evidence on day 5 of the trial of mr chauvin, the white former officer accused of killing mr floyd. here's a bit of what lieutenant richard zimmerman had to say, responding to questions from the prosecution. what is your, you know, your view of that use of force during that time period? totally unnecessary. what do you mean? well, first of all, pulling him down to the ground facedown and putting your knee on a neck for that amount of — that amount of time, isjust uncalled for. i saw no reason why the officers felt they were in danger, if that's what they felt. and that's what they would have to have felt to be able to use

that kind of force. our correspondent, lebo diseko, is in minneapolis and has been watching the trial. today has been very much about the police response. lt zimmerman, one of the longest—serving and most respected officers here in minneapolis, telling the court that in his 35 years on this force in minneapolis, he has never been trained to kneel on someone�*s neck and that is because it constitutes deadly force. also talking about the fact that once somebody is in handcuffs, they no longer constitute the same level of threat. and really saying that as a police officer, you have a duty of care to somebody once they are handcuffed, that their safety is your responsibility. major league baseball has announced it's moving its all—star game out of atlanta following the state of georgia's adoption of a new law that affects the right to vote.

critics of the new legislation claim it makes it harder for black people and other minorities to vote in elections. georgia's republican governor says he is "streamlining" voting procedures and "restoring confidence" in the electoral system. the announcement comes a day after president biden criticised the new law and called for the game to be rescheduled. the los angeles times baseball columnist bill shaikin wrote last week that major league baseball should move the all—star game. i asked him if he was surprised his advice had been followed. i am a little bit. major league baseball's been in this situation before. ten years ago, there was a controversial law in the state of arizona and the same calls were made, that there had to be a boycott, or major league baseball had to move the game, and they went on with the game as scheduled but socialjustice has changed a lot in america, especially after last summer and the summer of protests,

and a summer in which businesses and sports leagues vowed to listen more carefully to the public and to the athletes that play their game, and i think in this case, major league baseball was very aware that there wasn't really a need for a summer festival that would turn into a debate about voting rights, there was a clear right and a clear wrong, and there was a clear decision to be made, so rather than put out a strongly worded statement, major league baseball took action. that is really interesting. so by your argument, what you are saying is we could see more of these kinds of decisions in future? i think so. the folks in georgia that are upset about this law appealed to corporations across america to take whatever action they could and in this case, the difference is that coca—cola and delta — companies that are both based in the city of atlanta — they've come out with statements, but they are not about to move their headquarters and cost thousands

of people theirjobs. in this case, major league baseball had a simple action, move one game, it's mostly an exhibition game anyway, it doesn't really count for anything in the standings, with the idea that if this law is changed two or three years from now, major league baseball can bring the game back. i should just say, just for people who don't follow baseball, could you tell us in a couple of sentences, what actually is this game? it's called the all—star game, it's essentially a practice game. it's a showcase for the game's best players and whether you win or whether you lose, it does not matter, so it gives fans a chance to see their favourite players every year in one game. the best teams and the best players from the national league, the best players from the american league which are the two leagues that make up major league baseball in the united states.

let's get some of the day's other news. taiwanese prosecutors have sought an arrest warrant for a construction site manager whose truck is suspected of causing a train crash in which at least 50 people died. the train hit the lorry after it slid onto the tracks from a nearby building site. the train was packed with local tourists travelling to celebrate a local holiday and is the island's worst rail disaster in decades. officials from tehran and washington will travel to vienna next week, as part of efforts with other world powers to revive the 2015 iranian nuclear deal. the us and iran are not expected to hold direct talks. but russia has said the talks are on the right track. the iran nuclear deal was scrapped by president trump's administration, after he accused tehran of breaking the conditions. this is bbc news, the latest headlines: police guarding the capitol building in washington have shot and killed a man who drove his car into two police officers. one of the officers has died.

a minneapolis homicide investigator has said police officer derek chauvin used "totally unnecessary" deadly force when kneeling on george floyd's neck during an arrest last may. new research suggests the asteroid impact that killed off the dinosaurs also gave birth to our planet's tropical rainforests as we know them. a group of scientists has spent the past two decades investigating fossil leaves and pollen from across colombia and has finally gathered enough data to publish its findings. paleobiologist, dr monica carvalho from the smithsonian tropical research institute is one of those researchers and joined me to explain the study. we found that after the impact, or with the impact, 45% of tropical species disappeared, and it took about 8 million years for diversity to recover. crosstalk.

sorry — 8 million years is obviously a huge expanse of time, and when it did come back, what was different? forests were very different. so forests that came back resemble a lot rainforests that we know today, they were dominated by flowering plants, they were very dense and they had the same levels of intense ecological interaction that we see today. in the age of dinosaurs, that was not the case. the dominant plants were not flowering plants, it was a mixture of ferns, conifers and flowering plants, and it was actually a pretty widely open rainforest back then. i see. and why the difference, why the change do you think when it came back finally after all those millions of years? that's the key question. so... we're not exactly sure, we think that it could be

a mixture of factors, it could be that in the past dinosaurs actually helped keeping the forest open, something very similar to what happened in the african savanna with large elephants knocking down trees. it could be that there was a selective extinction against conifers in the tropics during the extinction event, or it could be that the asteroid's impact, all the ash and the vaporised rock and dust that was thrown out into the sky, fell down again and acted kind of as a fertiliser, that enabled flowering plants to actually take over. our thanks to monica carvalho there. to algeria now where thousands of anti—government protesters took to the streets in the capital algiers, demanding democracy, fair elections and independent judiciary. the country's protest movement was interrupted by the coronavirus pandemic, and these latest demonstrations mark a resumption in

the so—called hirak movement. dozens of activists remain behind bars, despite the current president tebboune�*s promises to overhaul the country's institutions. danai howard reports. thousands filled the streets of algiers on friday, chanting long live an algeria that is not military. they're calling for an overhaul of what they say is a corrupt political system and an end to the army's involvement in politics. friday's demonstrations mark the resumption of the weekly street protests that were suspended last year because of the covid—i9 pandemic. their determination has not waned. translation: the algerian people are still thirsty - for freedom, they're still searching for complete independence. translation: the people take to the streets today _ to save algeria from the hands of the ruling gangs, and to allow the people to regain their sovereignty

so that they can be free in theiraffairs, freedoms, human rights. justice is a popular demand. the leaderless protest movement known as hirak began two years ago and changed the face of alegria's leadership. in november 2019, widespread protests pushed the military to oust the former president abdelaziz bouteflika, who had been the country's leader for nearly 20 years. a month later, abdelmadjid tebboune was named algeria's new president in elections that saw a record 33% low voter turnout. protesters then and now say those election were a charade. in a bid to quell the protest movement, president tebboune recently pardoned dozens ofjailed activists and says he will reform the government, but that has not been enough for these demonstrators who see his government as a continuation of the leadership they have been fighting against for more than two years. danai howard, bbc news.

a russian medical team has successfully completed open heart surgery on a patient, as firefighters battled to control a serious fire at a hospital in the far east of the country. the leader of the heart unit said his team had to do everything to save their patient. gareth barlow reports. as smoke billowed out of the building, firefighters rushed in. emergency services scrambled to evacuate more than 120 patients being treated at the tsarist—era hospital. amid the chaos, one team of medics valiantly carried on. eight doctors and nurses performed a two—hour open heart operation. with electricity cut by the fire, an emergency power cable was fed into the building to keep vital life—support systems operational. translation: when smoke came in, we installed special— electric fire brigade fans to evacuate the smoke

from the first floor and from the operation room. the operation was a success and the patient safely transferred to another unit. no one was injured by the fire. however, the impact of the blaze will be keenly felt as the hospital is the only in the region with a specialist heart unit. gareth barlow, bbc news. to new york now, where the city's famous broadway theatres, art and entertainment venues are beginning to reopen at limited capacity. theatres have lain empty as the city battled against the covid pandemic, but from friday, theatres are allowed to reopen at 33% capacity. new york city's mayor, bill de blasio, says he's keen to get theatres back up and running again, with a full reopening by 2021. kelsey lu is a cellist in "this is not a test", performed at the shed threatre, one of the first venues in new york to reopen this weekend. she spoke to me

a little earlier. i never knew that i would be as excited to perform again as much as i am now in this lifetime. any nerves at all, not about the performing because i'm sure you're not nervous about that, but the limited audience and the procedures that everyone has to go through to get the performance up and running? i think that at this point we are all pretty used to having rules and regulations, but i think what really matters is the music, and that's what shines through and the energy that is in the room, and everyone just being excited to perform again, and to see something that we've all missed for so long. and so yeah, that probably is going to be a little jarring, but once it all starts, that will dissipate and fade away.

and how has this period been foryou, i'm presuming the longest period without playing and performing in your career? yeah, it has been honestly incredibly depressing. i mean at first it started out pretty nice because i hadn't had so much time to myself, and not being on the road and touring and i felt this new surge of energy and inspiration. and then the loneliness and everything that, i don't know, time that i was faced with, that performance is such a huge part of living and thriving for me. it is my lifeline, and having that exchange of energy between audience and people, and it really started to affect me, and my mental state, so i was yeah, it was really, really hard. i just want to pick up,

the importance of performing to that audience for you and your mental health, and it's going to be strange, not going back to what it was before, this is not thousands of people, this is a much smaller number, does that affect how you approach the performance? no, not at all. i mean that's how i started performing, i didn't start performing for thousands of people, i started performing for a few people. i started performing for small groups and intimate settings, and i love intimate settings. i think that's a special thing, and so i think also in that case, you are able to maybe even connect with people on a deeper level. so no, i don't think that would affect anything at all. kelsey lu there. all around the world, despite the global pandemic, millions of people will be marking the easter holiday. it is of course one of the most important dates

in the christian calendar, but plenty of non—believers will be celebrating too. for them it's more about confection than resurrection, as the bbc�*s tim allman explains. the easter bunny gets everywhere these days. here he is underwater off the florida keys. well, actually, this is captain spencer's slate, a local scuba operator. he is setting up a somewhat elaborate aquatica easter egg hunt. it is all for a good cause, raising money for local children in need. and in case you were wondering, all of the eggs have non—toxic colouring and are environmentally friendly. speaking of eggs, take a look at these. in hungary, there is at these. in hungary, there is a long easter tradition of decorating them. intricate designs, delicate paintwork,

little oval works of art. translation:- little oval works of art. translation: 5:2 , ., , translation: over 30 years i have got to — translation: over 30 years i have got to know _ translation: over 30 years i have got to know the - translation: over 30 years i have got to know the egg - translation: over 30 years i have got to know the egg as i translation: over 30 years i have got to know the egg as a| have got to know the egg as a material to work with. it may be very thin but it is still malleable so we know each other, the egg and i, me and the egg. other, the egg and i, me and the en ., , , ., other, the egg and i, me and thee“. , ,., ., ., the egg. these eggs at london zoo aren't _ the egg. these eggs at london zoo aren't quite _ the egg. these eggs at london zoo aren't quite as _ the egg. these eggs at london zoo aren't quite as impressive | zoo aren't quite as impressive but they do theirjob. every year, treats are hidden away by the keepers and then be monkeys go looking for them. and not just the monkeys, the meerkats also like to get involved. across the other side of the world, a similar story at this park in new south wales. the local wildlife getting into the swing of things. although, this koala still prefers eucalyptus leaves to easter eggs. tim allman, bbc news. that is it from me, i will be back with the headlines in a couple of minutes' time. i'm @lvaughanjones. i'm lewis vaughn jones.

you've been watching bbc news. goodbye. hello there. it's likely to be a dry day for most of the united kingdom today but there will be contrasts. where we keep the cloud as we had yesterday, temperatures will be held into high single figures, but in the sunshine, potentially 14—15. now, under the starry skies, that's where we see the frost as we start this saturday morning, but you can see the thicker cloud across northern scotland, central and eastern england, perhaps east wales. and there could also be a little bit of mist and fog where we've kept the clear skies as well. but the day is likely to give us quite a bit of cloud across central and eastern areas. it's likely to lift a little as we go through the day similarly so across northern scotland, we keep quite a bit.

for the likes of lincolnshire, east anglia and the south east, though, it could remain overcast all day. and with that keen breeze still quite gusty through the channel, only eights and nines, but 13—15 in the sunnier spells. now, as we go through the evening and overnight, we tend to thicken our cloud in the north, but under the starry skies elsewhere, again we can expect a touch of frost. but you may have noticed the approach of some rain for the north of scotland, and that's the start of the transition to much colder air. it's this particular weather front here, as you can see, and behind it, there's arctic air following. so, we are going to have another blast of cold air as we head through in towards easter monday, but for sunday, easter day, a little bit of mist and fog around. actually, we should see a bit more sunshine for england and wales, but cloudier skies with rain for scotland followed by snow and cloudier skies for northern ireland. eventually, we'll see some of that wet weather coming in through the afternoon. but notice the temperatures. we've lost that keen north—easterly. they're a little bit higher temporarily. but overnight sunday into monday, that weather front introduces that colder air right the way across the uk, an arctic blast for all of us. and notjust the cold air,

but a strong to gale—force north wind, as well, which will accentuate the chill. clearly, the showers are quite prevalent for northern scotland, but they may well work their way down through the irish sea, down the east coast of both england and scotland as well. but there should be some sunshine between, but itjust will feel much colder, more like winter. these are the temperatures on the thermometer, but you add so, big changes afoot, and that may well last into the start of the new week into tuesday, as well, as you can see. as ever, you can keep up to date on the weather on the website. that's where all the warnings are. bye— bye.

this is bbc news,

the headlines: a police officer has been killed in an attack near the us capitol building in washington, after a man drove his car into two officers before getting out of the vehicle and lunging at them with a knife. the man was then shot by police — he later died. a minneapolis homicide investigator has said police officer derek chauvin used "totally unnecessary" deadly force when kneeling on george floyd's neck during an arrest last may. mr chauvin denies the charges against him. police have been questioning the manager of the construction site whose truck is suspected of causing a train crash in which at least 50 people died. the train hit the lorry that slid onto the tracks from the building site causing hundreds of people to be trapped for hours.