this is bbc news, broadcasting to viewers in the uk and around the world. i'm nancy kacungira. the headlines... russia steps up its bombardment of large parts of ukraine, as nato warns the conflict, is about to get worse. we'll be reporting from inside the country's second biggest city, harkeev, where residential buildings have been reduced to rubble, by constant russian shelling. europe's largest nuclear plant is shelled by russian forces overnight. the fires are under under control. ukraine says moscow is resorting to "nuclear terror". translation: we need to stop | the russian military immediately. scream to your politicians. ukraine has 15 nuclear units, and if there is an explosion it is the end of everything. and at ukraine's borders, the refugee queues grow longer, more and more people are trying to flee. hello, and thank you forjoining us. the united nations security council is holding an emergency meeting to discuss the way in which russian forces captured ukraine's biggest nuclear power plant. the un's political affairs chief has said attacks on nuclear power facilities are contrary to international humanitarian law. the zaporizhzhia facility was sheued the zaporizhzhia facility was shelled this morning triggering a

fire. the authorities say the site is secure and radiation levels are normal. the ukrainian foreign ministry say several people have been killed and injured. the plant is in the south east of the country and the biggest in europe. president zelensky has accused moscow of resorting to "nuclear terror" and urged russians to protest. russia has escalated its air campaign against ukrainian cities throughout the last 2a hours. an official in the besieged port of mariupol has accused russia of trying to force it to surrender by creating a humanitarian crisis. he said the city was being shelled continuously. it's facing a third day without water, electricity, or proper sanitation. kharkiv in the north east has been reduced to rubble. and ukraine says at least 50 people were killed by russian air strikes in the northern city of chernihiv. the polish border guard agency has confirmed more than 672,500 people have fled ukraine to poland since

the war began last week. more than 99,000 people crossed the border yesterday. meanwhile, the nato alliance has rejected calls from kyiv for it to impose a no—fly zone over ukraine, saying this could lead to a wider war with russia. 0ur eastern europe correspondent sarah rainsford has this special report from inside kharkhiv, which has been bombarded by russian forces this week. as we drove into kharkiv, it looked like half the city was heading out. a flow of families who have endured days of bombs and explosions. many wrote the word "children" on their cars, hoping they wouldn't be targeted. a few miles on, others stood with bundles of belongings, waiting for a bus to take them out, any bus to anywhere. svetlana told me shells had been adding close to her home. landing close to her home. i asked how she's coping.

she said isn't. it's been a week with barely any sleep. this is what is keeping kharkiv awake, two days ago there were homes and businesses here. we saw no sign of any military facility. just more destruction across the road at the local shops. and men searching for medicine among the ruins to use for soldiers. "it is scary but this is our city," maxim tells me. "we don't want to run anywhere." so, ukraine's second city has moved underground. their whole lives now playing out on these platforms. and on trains that stopped when the war began. above ground, shops are running out of food. down here, people live off hand—outs. i really... it's scaring myself and my family. so, we take documents and just came here. so, now, thousands of people are living underground like this

here in kharkiv for more than a week now. and the parents are trying to make it as normal as possible for their children. they've brought toys, they're getting food down here, but this is so far from normal, it's kind of hard to even describe. and these people have no idea what they're going to do next. this family has been down here for three whole days now. translation: we hope for the best | but we are prepared for the worst. l at least we have food and air and the children are ok. the power is down in this region, so we found people tapping into the mains from the metro in the underpass. charging their phones, a vital connection to the outside world. these couples had surfaced for air because they said the concentration of grief underground was too much to bear. translation: it's scary because we don't know. what's coming tomorrow. nothing is changing here. nothing is happening.

kharkiv has already suffered so much but it fears this war has barely started. a city of russian speakers who can't fathom why russia is now destroying their lives and their houses. sarah rainsford, bbc news, kharkiv. russian forces are steadily making gains in this war, as urban areas are cut off by troops. in the city of mariupol in the south, which is under siege, the mayor says food is running out and there's no water, heating or electricity. the russian advance is also gaining momentum to the east and north, with continued shelling and artillery fire that we can and artillery fire. jeremy bowen has more. across ukraine, russia is trying to bring its strength to bear.

this was borodyanka, north—west of the capital. not much is left standing in one of kyiv�*s satellite stands. fierce ukrainian resistance. the russian�*s army answer to that is fire power. and after a night of fighting much further south, russia has seized the nuclear power plant at zaporizhzhia, the biggest in europe. the reactor is safe, but it's hard to imagine a worse place for a firefight. kyiv railway station is the gateway to relative safety far west near the polish border. and it's the start of separations. no one knows how long they'll be apart. 50,000 people a day crowd the lviv platform, almost all women and children. translation: i'm really i worried about my three kids and i want to come back. but now i'm very scared. people shout.

i head up to 12 hours ground into an overcrowded carriage on the most uncertain journey of their lives. the people who couldn't fight their way on board waited for the next one. they grab what mattered most to them, and there's the pain of parting. all the heartbreak of the war was on alexander's face. he'd just put his wife and two small children on the train. he wouldn't let go of a toy ambulance his eight—year—old son has given him as he said goodbye. men have to stay to fight. this man used an app to translate for us his attempt

to reassure his wife. she also asked me to leave. i said we will fight to the end, it will be easier for us - to fight when you are safe. no one knows theirjourney's end. the evacuees or the husbands and fathers they left behind. 0n the edge of kyiv, some volunteers are in position, still trying to get organised. the professionals — better armed and trained — are closer to the front. kyiv is the biggest symbol of ukrainian independence and that makes it the biggest target for the russian army. they are still a reasonable distance in that direction. the city is there. it's big and it's sprawling, and in a lot of people's minds here at the moment is the question of whether president putin will order the kind of assault on the capital that he has ordered on cities elsewhere in the country. first lesson for the new soldiers —

loading bullets into a magazine. most at this territorial defence centre were boys of 18 and i9. i study economy. and i am studying biology. they have the same patriotism, courage and sense of invincibility of other generations of young men who volunteered to fight in europe's wars. their parents will pray they don't learn the same brutal lessons. the older men were more apprehensive. they shout together. 0n the bus, they all cheered for victory and death to their enemies. jeremy bowen, bbc news. as we have been hearing, the attack on the zaporizhzhia plant led to

global condemnation. there's no indication of increased levels of radiation in the area, but the international nuclear watchdog says it's deeply concerned. 0ur science correspondent, victoria gill, now takes a look at what those concerns might be. warfare at a nuclear power plant. the blaze, which was quickly extinguished, was in a training facility. and, critically, it didn't affect any of the six nuclear reactors. the reactor building complex is about a kilometre long and now only one of the reactors is reported to be operating, with the rest safely shut down. we, of course, are fortunate that there was no release of radiation and that the integrity of the reactors was not themselves compromised. ukrainian emergency crews tackled the fire, but nuclear experts say the situation is still precarious. we're not looking at another

chernobyl accident, but the primary concern here is that the electricity supply gets cut off, it stops the pumps from working that cool the reactor. and if that were to happen, the nuclear fuel inside would melt down, so it's really important that the russian forces and the ukrainian forces stop firing in the direction of the power stations. this loss of cooling was what caused the nuclear disaster at fukushima injapan in 2011. but while that was triggered by a natural disaster, a tsunami, the invasion of ukraine has brought conflict close to working nu clear rea cto i’s . with the russians now controlling the site, the immediate danger has passed. but concern remains over why a nuclear plant was a military target. victoria gill, bbc news. for more on this i am nowjoined by matthew kroenig in washington dc. he is a nuclear expert at the atlantic council. as an expert in this field, how alarmed were you when you heard this

nuclear plant have been attacked? i was very alarmed. this is the first time in history that a country has intentionally fired on a nuclear plant. we have had accidents in the past at chernobyl, three mile island, fukushima, but they were accidents or acts of god. this was an act of war. it could have been quite bad. it could have led to an meltdown, it could have led to nuclear material being dispersed in the area, so it seems like we are in the area, so it seems like we are in the clear for now, but ukraine has 13 nuclear power plants, there are still fighting going on in the vicinity of this one, so i remain concerned this is quite serious. tell us more about those concerns because we have heard this is still a precarious situation. can you tell us why that is. the a precarious situation. can you tell us why that is-_ a precarious situation. can you tell us why that is. the radioactive core of a nuclear —

us why that is. the radioactive core of a nuclear power _ us why that is. the radioactive core of a nuclear power plant _ us why that is. the radioactive core of a nuclear power plant is - us why that is. the radioactive core of a nuclear power plant is very - of a nuclear power plant is very hot, and in the spent fuel rods, after they are run through the reactor are hot, and they are on site and so there are elaborate cooling systems to keep them from melting down. but if the plant comes under attack, melting down. but if the plant comes underattack, if melting down. but if the plant comes under attack, if the systems lose power, if there is a crack in the vessel that contains the water for the cooling, then those systems could fail. that is what we saw at fukushima. the term nuclear meltdown comes from the fact the car or the fuel could literally melt down into the earth, into the water supply. this reactor is right on the dnieper river. it is quite common to site reactors on the river because they require a lot of water, but that would mean the nuclear radioactive material could flow into the black sea so it could be a very serious disaster. 50 sea so it could be a very serious disaster. ., , sea so it could be a very serious disaster. . , ., disaster. so a big risk here that an hinu disaster. so a big risk here that

anything happens _ disaster. so a big risk here that anything happens to _ disaster. so a big risk here that anything happens to stop - disaster. so a big risk here that anything happens to stop them | anything happens to stop them calling down, but it is still unclear it was a deliberate target, the nuclear plant, is that right? that's right. when i first heard the news last night, i wondered if the russians were intentionally trying to cause a nuclear disaster. it seems that as there campaign has slowed they have turned to the deliberate targeting of civilians and this would certainly be an act of terror. even just the fears that the reactor could meltdown have caused a lot of terror. but now they have taken control of the plant, i'm beginning to wonder if maybe the goal is to control the plant. it provides about 20% of ukraine's power, so if russia threatens to turn off the power, they could use that as a tool of coercion to strengthen their own hand and weaken the ukrainians in the war. mi the ukrainians in the war. all riaht, the ukrainians in the war. all right. that — the ukrainians in the war. all right, that does aid our understanding. thank very much.

matthew kroenig, a nuclear expert at the atlantic council. the humanitarian situation just gets worse, day by day, hour by hour. the united nations is now warning that on top of the one million refugees who've already fled, millions more could be forced from this country if the fighting is prolonged. this map shows the extent of the exodus. the larger the arrows, the greater the population flow. refugees are crossing into neighbouring countries to the west. more than 100,000 people have fled to moldova, and our correspondent lucy williamson reports from the palanca border crossing point, about 30 miles from the ukrainian port city of odessa. when 0desa flinches, palanca catches the blow. the fear in ukraine's southern city is reflected in the queues, the emotions spilling out at this once little—known border post. a bus to an emergency shelter oversubscribed. an official loses control. "there's a five—year—old waiting,"

he shouts, "move back." svetlana had been waiting for a visa to join her husband in the uk. with the conflict spreading and her passport stuck at the british embassy in lviv, she's crossed into moldova without it. "it is impossible to understand what has happened," she said. "we're living in the 21st century. "people are just hoping for the best and holding on to the end." katya also arrived today from 0desa with her sister and three children. after they saw a ship destroyed in a huge explosion. translation: the kids - were asking, "what's going on?" and we said it was fireworks. what are you going to say to a kid? you can't tell them it's a war out there. video from 0desa this week showed the men behind filling sandbags, ready for a russian invasion. russian landing craft were spotted off the coast yesterday. and today, at 0desa's

train station, panic. the numbers here are being driven by russian operations in the south of ukraine. this border is squeezed between two separate wings of ukrainian territory. the refugee agencies here say that if 0desa comes under attack, these numbers will surge again. the eu's head of foreign affairs says this migrant crisis could dwarf the last one europe faced, in 2015. in 2015/16, europe was shocked by one million people coming from syria. now, in four days, we already have almost one million people. and ukraine has a0 million people. if the russians continue bombing the city in the way they are doing, if we're ukrainian, what do we do? each day at palanca, thousands make that same calculation. the same half—solution to war. crossing a border might

protect you from danger, it doesn't always protect you from fear. lucy williamson, bbc news, moldova. that's the situation in moldova. let's have a look at what is happening in poland. the numbers feel overwhelming. when you talk about over one million people having left ukraine fleeing their country from the fighting, it feels like a number that is just unimaginable. when you think about over 700,000 people have fled ukraine to comejust to poland alone, it's difficult to comprehend, but when you see what is happening on the ground, this is one border crossing. 0ne snapshot of a long border. and these scenes are repeated time and time again. thousands of people crossing the border every single day. this is just one crossing across this long, long border

between poland and ukraine. and then when the people come, they're tired, they're exhausted. they've had very long journeys. they come here and they wait for the next part of theirjourney. they wait for transport to take them on to the next reception centres where they're able to gather their thoughts, get something to eat and then think about what happens next. now, the uk home secretary priti patel was here on the border. she was on the very border itself. she didn't come here, she didn't see this, but she was on the border itself. and she spoke about the ukraine family scheme, whereby ukrainian nationals who are settled in the uk can bring family members over. but when you look at the sheer scale of the number of people who are coming over all the time, this is day after day after day. we've been here since saturday and the scenes don't change. is it enough? the eu has opened its borders. it's talking about a longer term process because it understands that these people will be here for some time, given the uncertainty of what is happening

back in ukraine. it's talking about a temporary protection directive so that the people that are coming over who have had to flee their homes can work, can get access to medical care, can get their children into schooling in other countries within the eu. the figures are simply overwhelming, and the fear is that they will continue to grow. we can speak now to howard mollett, who's the director of humanitarian policy for the international catholic charity, cafod. thank you for talking to us. your network of churches is playing an important role because while many international aid agencies have been able to get to the east, in the west and central areas it is local organisations and national ones like yours that are really playing a big role. tell us about the situation there at the moment from what your

partners are saying to you. absolutely, and thank you for drawing attention to this because there's not enough recognition i think at the incredible amazing brave work by local community groups, networks of volunteers, local ngos across ukraine. it is really them helping people to survive, getting food, blankets, other items to people that need them, and also advising people on how to flee and reach a place of safety. actually it is in that context that i want to flag about the british government has made some pledges on aid but the vast majority of that is to the un system. un agencies obviously have an important role to play but they are not present and definitely not... notoriously not the best at partnering with local community groups, top—down bureaucratic and so on. that's why cafod is part of the d easy appeal to get funds directly

to local community groups including church groups —— the dec appeal. we also think they should reflect on how they can learn from this crisis and other ones like syria where it was community networks and local ngos at the front line of saving lives. . , ., ., , ngos at the front line of saving lives. . , . ., , ., lives. that is a really important oint, lives. that is a really important point. and _ lives. that is a really important point, and talking _ lives. that is a really important point, and talking about - lives. that is a really important point, and talking about somel lives. that is a really important l point, and talking about some of lives. that is a really important - point, and talking about some of the high level discussions happening, obviously there was an agreement on a humanitarian corridor. how are you feeling about how that will affect the operations you are carrying out with your partners? we the operations you are carrying out with your partners?— the operations you are carrying out with your partners? we are hearing directly from _ with your partners? we are hearing directly from partners _ with your partners? we are hearing directly from partners in _ with your partners? we are hearing directly from partners in ukraine i directly from partners in ukraine that they do want guarantees for safe —— passage, both for people fleeing and for aid workers doing their work but they have serious concerns about how genuinely safe these so—called humanitarian corridors will be and whether they might also put people at risk. for example... i5 might also put people at risk. for example- - -_ example... is one concern that

russia won't — example... is one concern that russia won't keep _ example... is one concern that russia won't keep their - example... is one concern that russia won't keep their word? | example... is one concern that - russia won't keep their word? what we have seen _ russia won't keep their word? what we have seen in _ russia won't keep their word? what we have seen in syria _ russia won't keep their word? transit we have seen in syria and ethiopia and elsewhere is that where there are these humanitarian corridors in theory put in place, they then become an excuse to indiscriminately bomb people that are left behind. we saw this in syria where the syrian regime besieged towns. even evacuations were attacked, then this was used as an excuse to bomb city to the ground and kill and arrest people left behind. also i dop as well as in syria, we saw that the un and diplomats from the uk and elsewhere got into what we could call truck counting on these humanitarian corridors, so sort of x number of trucks promised over a certain time frame. the promises never materialising, and the diplomats and the un losing sight of the bigger picture which was people

being starved to death, cities being bombed and people being forced to flee from their homes, so we hope the humanitarian corridors might translate into safe passage but we need to ask questions about how they will be monitored. will there be an international presence on the ground doing the monitoring? who will be left behind? will there be safe passage for men of fighting age and so on? so these are some of the concerns. so on? so these are some of the concerns-— concerns. and those are very big concerns. _ concerns. and those are very big concerns, thank _ concerns. and those are very big concerns, thank you _ concerns. and those are very big concerns, thank you for - concerns. and those are very big concerns, thank you for sharing | concerns. and those are very big - concerns, thank you for sharing them with us. howard mollett, who's the director of humanitarian policy for the international catholic charity, cafod. that is the update we have on the developing situation in ukraine after the russian invasion. we continue to bring you the update and you can stay up—to—date on our website, minute by minute updates. stay with us here on bbc news.

good evening. it has been a day of mixed fortunes for many. we have seen quite a lot of cloud around and yes, at times it has been wet. this was lincolnshire this afternoon. it never really progressed above the low cloud, mist and murky story and there has been rain cringing away from eastern scotland, certainly sitting to the east of the pennines down to the south—east corner. behind that, there was quite a clearance and lovely spells of sunshine to be found. this was cumbria a few hours ago. it looks likely that the drier and brighter story will win out as we go through the weekend. a little bit more sunshine around but overnight frost and fog could be an issue as we go through the weekend. 0ver and fog could be an issue as we go through the weekend. over the next

few hours, that weather front will grind to a halt across the far south—east corner, but high pressure builds in behind and that will keep this guy is clear and temperatures will fall away like a stone across scotland, northern ireland, northern england and parts of wales. here we will see temperatures just below freezing. down into the south—east corner underneath that cloud and those outbreaks of rain, temperatures holding up around five or 6 degrees. 0nce temperatures holding up around five or 6 degrees. once again it will start off grey, drab and dreary and some of the rain will drift further west through the afternoon. the best of the sunshine to start the weekend certainly the further north and west you are. more of a breeze at times and temperatures likely to hold up at a maximum of 10 degrees, so that isjust a at a maximum of 10 degrees, so that is just a little bit under par for this time of year. as we move into sunday, that high pressure hopefully starts to establish itself a little bit more across the country and finally the nuisance weather front we have seen for the last couple of days decays and eases away. more of

a breeze across the south and that could drive in a little more cloud, particularly first thing in the morning, but hopefully that will break into the afternoon. temperatures should peak at 9 degrees. as we move out of sunday into monday morning, it is certainly worth bearing in mind that with those clear skies the temperatures will fall away. it will be a cold and frosty start for many first thing on monday morning, but monday into tuesday, dry and settled and sunny for most, but those temperatures on the chilly side for the time of year.

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