welcome to bbc news, broadcasting to viewers in north america and around the globe. i'm reged ahmad. our top stories: the search for survivors intensifies in mexico city after an earthquake kills over 200 people. hurricane maria knocks out power to the whole of puerto rico, isolating more than 3 million people. a day after president trump called iran a corrupt dictatorship, president rouhani tells the un his country will not be intimidated. and human life and how it all starts — for the first time in the uk, scientists use gene editing on an embryo. in central mexico, teams of rescue workers are continuing to search for survivors, after a powerful earthquake claimed at least 200 lives. dozens have been saved

from the ruins of buildings which collapsed 2a hours ago. but the nation is mourning 21 children who were killed when their primary school collapsed. 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 120km south of the capital. our correspondent aleem maqbool is in mexico city where the rescue work is continuing. it is today the full scale of the destruction in mexico city has been revealed. more buildings weakened by the frightening force of the earthquake collapsed overnight. and this is just one of the terrifying dramas 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, i want 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. i was inside the building and it collapsed. everything came around. cctv footage from a shopping centre showed the roof start to collapse. this woman getting out of the wayjust in time. on their mobile phones,

people captured countless shocking videos of buildings collapsing. many who survived wandered around in shock. it is extraordinary that even though much 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 they began to raise their hands to ask for a few moments‘ silence to try to hear any cries for help. but no joy this time. people all over this city and beyond in the rural areas affected arejoining 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. translation: 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. well, let's stay with that story — our correspondent rajini vaidyanathan is in mexico city and she's just sent this report. well, the focus here in the la condesa neighbourhood of mexico city is on the rescue efforts. more than a day after the earthquake struck, people here in mexico city

are still taking in the horror of what exactly happened, but there is also huge amounts of hope. this building here was a 6—storey commercial and residential property. as you can see it was completely flattened. it isjust a big pile rubble and twisted metal now. but throughout the day rescuers have been picking through the remains, trying to find signs of life, and officials say they have rescued as many as 2a people from here, and they are not giving up hope that they will find more people. as well as that, hundreds of volunteers have also flocked to the area, many of them handing out bottles of water, handing out hot meals and medical supplies. there is still a sense of caution here, as many people fear the possibility of after—shocks and also there were gas leaks that happened in the wake of the earthquake and so many people here have been

holding up cardboard signs, urging people not to smoke and not use mobile phones, in case there may be gas explosions. in the wake of the earthquake in mexico city, as many as a0 buildings were completely destroyed, notjust here, in this neighbourhood, but across the city, including at a school in which many young children's lives were lost. a curfew has been imposed across the island of puerto rico. it brought wind speeds of up to 225km/h and the storm has weakened slightly as it moved across the island. the us virgin island of st croix has also been hit. communications with the island of dominica remain largely cut off but aerial photographs

show flattened buildings and fallen trees. 0ur correspondent will grant is in puerto rico and sent this update. 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 miles per hour 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. at the united nations in new york the us secretary of state rex tillerson and iran's foreign minister have held talks on the nuclear deal with tehran. javad zarif and the european union's foreign policy chief federica mogherini defended the nuclear deal between iran and world powers.

ms mogherini said iran was in full compliance of the agreement. donald trump has said the agreement was "the worst deal ever signed. earlier, the iranian president, hassan rouhani, said his country will respond "decisively and resolutely" if the united states walks away from the nuclear deal. translation: it will be a great pity if this agreement were to be destroyed by rogue newcomers to the world of politics. the world would have lost a great opportunity but such unfortunate behaviour will never impede iran's course of progress and advancement. as such, it belongs to the international community in its entirety and not only to one or two countries. let's take a look at some of the other stories making making the news. police in the uk have detained a sixth man in connection with last week's attempted bomb attack on a london tube train. in the last few hours officers arrested a 17—year—old man in south london — earlier, two men were arrested under the terrorism act in south wales.

the manager of england's women's football team, mark sampson, who's been embroiled in allegations of racism and bullying, is to step down. the 34—year—old left his role after evidence emerged of "inappropriate and unacceptable behaviour" during his time at a training academy. spain's prime minister has urged catalan separatists to respect the law after protests were held in barcelona against government attempts to halt an independence referendum. the leader of the catalan government accused the central government of ‘coordinated aggression‘ after 14 catalan officials were detained for organising the referendum. 0ur correspondent tom burridge spoke to some of those taking part in the pro—independence demonstrations. there‘s a real sense of defiance here. these people were already angry at the spanish authorities who have years blocked attempts to hold

a referendum on independence from spain in catalonia but as of today, the sense of political tension here has moved up again. we just want to vote. it‘s not like we are calling for independence. i want independence but wejust for independence. i want independence but we just want to vote and that is our right. everyone, what do you think, yes, i'io. everyone, what do you think, yes, no. spain is not going to allow a vote because they say it is illegal. we are going to do it anyway. like an with the british government and scotland, i cannot understand how spain is not letting us do that. the much of the time here, there‘s been kinder of an atmosphere. in the distance, from the crowd, is the economic minister of the devolved cata la n economic minister of the devolved catalan government. it was raided by government authorities in a high—stakes government authorities in a high—sta kes manoeuvre by government authorities in a high—stakes manoeuvre by the spanish state to try and prevent the referendum which madrid says would

be illegal from taking referendum which madrid says would be illegalfrom taking place. police came wanting to arrest people. it‘s made a lot of noise and everyone has had enough. it'sjust a joke to me that they are calling democracy and illegal thing. they can't stop us, evenif illegal thing. they can't stop us, even if they have the army, even if they have everything, they can't stop us. i don't really care about the consequences any more. like, i will have to print my own papers, i don't care what i have to do. this crowd, though, is not representative of wider catalan society. 0pinion polls in the past have been inconclusive when catalans have been asked whether or not they want an independent catalan state. despite the efforts of separatist parties to run the devolved administration here to force the spanish government‘s and, we have now reached an uncomfortable and unpredictable stand—off. stay with us on bbc news — still to come: his art now fetches record prices. a new exhibition celebrates the wild

world ofjean—michel basquiat. ben johnson, the fastest man on earth, is flying home to canada in disgrace. all the athletes should be clean going into the games. i‘m just happy that justice is served. it is a simple fact that this morning, these people were in their homes. tonight, those homes have been burnt down by serbian soldiers and police. all the taliban positions along here have been strengthened, presumably in case the americans invade. it‘s no use having a secret service which cannot preserve its own secrets against the world. and so the british government has no option but to continue this action, and even after any adverse judgement in australia. concorde had crossed the atlantic faster than any plane ever before, breaking the record by six minutes.

this is bbc news. the latest headlines: a powerful earthquake has killed more than 220 people in mexico. the search for survivors in collapsed buildings is continuing, including at a primary school. hurricane maria has torn a path of destruction across puerto rico. flooding and severe winds have knocked out power to the entire island. we can now speak to erick garcia barba. he lives in one of the neighbourhoods in mexico city that was damaged by the earthquake. can you tell us what your neighbourhood looks like at the

moment? some areas are ok, but as you come closer to the places where their buildings collapsed, you can‘t go there. me and my family, my wife and baby, went to try and help in any way to bring some groceries and some gloves and protection, and we weren‘t able to access, not even to the closest area but to the surrounding areas. fortunately, there are lots of hands working to try and help the people who are inside the collapsed buildings. the neighbourhood so far, this specific area is ok. this area in the south of mexico city, going north, about five or ten minutes away from here,

you can see buildings collapsed. this is not real. you have never experienced, you never think that you are going to experience a repeat of what happened in 1985. it wasn‘t as devastating, but this is like a dream. you don‘t believe this is real. you do still sound quite shocked, more than 2a hours after this earthquake. you mentioned you have been trying to help, we have been hearing that there is a huge volunteer been hearing that there is a huge volu nteer effort been hearing that there is a huge volunteer effort alongside rescue officials. tell us about that. one officials. tell us about that. one of my colleagues, he was helping out last night. i was having communication with him this morning. he told me that, he said, you have no idea of the feeling when you see somebody coming out from the collapsed buildings. my colleague

told me that he was about to cry, because there were three people rescued and more people afterwards. and this feeling is unbelievable. as you were saying, several people are working hard, trying to provide some help. thank god there are many people, mexican people and people from abroad, who are working and helping us out, the help that we actually need. as the rescue and recovery efforts continue, what is the main concern in the city? are people worried about tremors, access to food and water? the main concern right now is having access to the primary school. at least 20 kids we re primary school. at least 20 kids were rescued, but still kids died in

there. this is the main focus, some other buildings collapsed, but this is the main focus because you never think that this can happen to kids —— focus. think that this can happen to kids -- focus. we are keeping across the rescue in the priory school you have been speaking about, thank you for your time been speaking about, thank you for yourtime and been speaking about, thank you for your time and the best of luck to you. thank you very much and i can only finish with one final thought. mexico city is in pain, this is a really ha rd mexico city is in pain, this is a really hard experience and 200 people or more have died. thank you very much for being here, for providing this information, and we can... if people can keep trading, that would be great. -- praying.

for the first time in the uk, scientists have altered the dna of human embryos. the research — using a technique known as gene editing — was performed at the francis crick institute in london. it‘s aimed at increasing understanding of the first days of human development. 0ur medical correspondent fergus walsh reports. 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 oct—4 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 crisper, into each of them. now, the crisper system scans the billions of letters of dna like a spell—check, until it gets to the oct—4 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. 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. 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. before banksy there was basquiat — a graffiti artist who became a sensation in the art world. now the first large—scale exhibition of his work is going on show at the barbican in london. 0ur arts editor will gompertz reports. there‘s no mistaking a jean—michel basquiat painting, there‘s that sense of improvisation, the crudely drawn figure and the graphic, poetic rhythms which are like a pictorial form of free jazz. it‘s a visual language, partly inspired by picasso and partly by new york‘s street art scene in the late ‘70s — in it which he was a major player — producing work that continues to be influential to this day. i think it‘s definitely true to say that a lot of artists working on the street today take a lot

of inspiration from basquiat‘s work and his attitude to public space. when he made his work on the street, he particularly made it around the soho district where the galleries were. he wanted his work to be seen by the media, by the galleries. he was a man with a plan? i think he was a man with ambition. he became a well—known character on the scene. he started to make drawings, he made friends with andy worhol and then, as he turned 20, made the very tricky transition from street artist to fine artist. he saw that his art career was just going to be, you know, massive. he knew that. he knew he was going to be famous from the very beginning, the first time i spoke to him. the rest of us, we were like making our art and trying to impress the other 300 or 400 people that were downtown on the art scene. basquiat was looking well past that, he was looking at global domination. he became the toast of manhattan‘s super wealthy collectors. he was called thejimmy hendrix

of art, the post—modern picasso, but he was, and for a long time after his death in 1988, largely overlooked by the art establishment. partly that has to do with him being black. there really wasn‘t a black presence at the highest levels — blue chip levels — of the art world ,and also the sense of, like — you know, black people, you‘re great at the singing and dancing and all that, but the conceptual stuff, leave that to us. you know, leave that to white europeans. and that‘s really offensive and that alone made jean crazy. jean—michel basquiat‘s hybrid artworks with their raw combination of graffiti drawing and abstract painting synthesised the political, social and cultural landscape of america in the late ‘70s and ‘80s with a veracity and power few others could match. will gompertz, bbc news. stay with us on bbc world news.

hello. the very same weather system that produced a very wet wednesday in northern ireland is gradually pushing further east across the uk during thursday. here it is. at least to begin the day, there will be heavy rain bursts in western areas. we are looking at things at eight o‘clock in the morning. you can see it in the west of wales into south—west scotland. all points east of that should be fine and dry. a mild morning compared to wednesday. but the overnight rain is pushing away from northern ireland. something sunny not far away. it is a bit lighter the further north you are. some of us in eastern scotland will start the day dry. it is very slowly going east. even by the end of the afternoon it won‘t be into eastern england. ahead of this weather system, in some sunshine, feeling quite cooler. but the sun will come out. northern ireland, scattered heavy showers. some pushing in the western parts of scotland through the day, especially into the western isles. that weather system is just creeping into western

parts of eastern england that stayed dry on thursday. thursday night, a chilly night into friday morning. widely into single figures, low single figures in some spots, a few patches of mist and fog. northern ireland, another system of weather coming in with rain. a gale in the irish sea. that rain is gradually edging into other western and northern parts of the uk into friday. again, leaving much of central and eastern england dry. pulling away from northern ireland, with sunny spells coming back. the weekend starts with a frightening area of low pressure, but most of the energy is pushing away to the north.

a weaker weather front heading our way slowly as the weekend goes on. a gale in places. a mild breeze blowing elsewhere across the uk. sunny spells developing from the south. the odd spot of rain shifting northwards through the day. a weather front weakening in the west of the uk. ahead of that, we‘ll see the higher temperatures. some spots are into the low 20s perhaps. hurricane maria is out of mexico and is moving close to the north—east coast of the dominican republic. it could be a major hurricane cloe to the turks and caicos islands by friday. this is bbc news, the headlines: the search for survivors of the mexico earthquake continues, with emergency crews and volunteers digging through rubble with their hands. more than 200 people are known to have been killed across the country, including at least 21 children at a school in mexico city. dozens more children

are feared to be trapped. emergency officials in puerto rico say hurricane maria has knocked out power to the entire island which is home to 3.5 million people. the head of the disaster management agency said it had damaged everything in its path. the iranian president hassan rouhani has condemned president trump‘s speech to the un, in which he called iran a "corrupt dictatorship" that exported violence throughout the middle east and beyond. speaking at the united nations general assembly president rouhani called mr trump‘s comments "ignorant and absurd". now on bbc news, click. this week, the technology helping american schools to prepare