this is bbc world news today. i'm lucy grey. our top stories: they're calling it the march for their lives, hundreds of thousands of young americansjoin rallies across their country in support of stricter gun controls. in a little over six minutes, 17 of our friends were taken from us, 15 were injured, and everyone, absolutely everyone, in the douglas community was forever altered. the security chief in the egyptian city of alexandria has been targeted by a car bomb. he escaped unhurt, but two policeman were killed. australia's cricket team is in turmoil, as one of the team admits he tampered with the ball in the test against south africa. but the captain says he won't resign. being the leader of the team, i'm incredibly sorry for, i guess, trying to bring the game into disrepute. and it's lights out for earth hour. cities around the world take the symbolic step to raise awareness about climate change. hundreds of thousands

of students and campaigners have gathered in cities across america, for rallies pushing for tougher gun laws. the protest called "march for our lives," was led by survivors of the massacre at a school in florida last month. they've been addressing crowds around the country, including in washington dc, and vowing to "stop at nothing" until lasting change is made. here's our north america correspondent gary o'donoghue. they came from across the country, bringing their message to the centre of power in the nation's capital. one of the biggest gun control demonstrations in years. parents, students, teachers, with a unified message, put an end to school shootings. we are marching because it's time for a change.

i do not want to be a pager that has guns in my building. no guns in schools, no guns in churches, no guns in the workplace. one of those determined to make the march today was lauren, who was just six when 20 of her school friends died in the shooting at sandy hook elementary school, in 2012. it's fairly depressing because it's like this should have stopped a while ago. it's been very consistent. really, it should just end. america is used to school shootings, but the murder of 17 students and teachers at the parklands school in florida on valentine's day has galvanised a new generation to take direct action. parklands students have already affected changes in the law in florida and as the president was heading south to his florida home, students from there came to washington to ask congress to do more. they know it's coming, they know that there if there is no

assault weapons ban passed, then we will vote them out. cheering. they know that if there is no tightening of the background checks, we will vote them out. cheering. they know that if there is no shrinking of magazine capacity, we will vote them out. scenes like this have been replicated all over the country with marches from los angeles to boston. and it's not just confined to america. across the uk, young people marched in solidarity. congress has passed some modest measures in the last few days but nowhere near the sweeping reforms these protesters are demanding. gary o'donoghue, bbc news, washington. well, one of the speakers at the rally was emma gonzalez, one of the most vocal students who lived through the shooting at marjory stoneman douglas high school. she took to the podium

and spoke of the time it took for the shooting to end — six minutes, she said, which left everyone in the school and the wider community changed forever. for those who still can't comprehend, because they refuse to, i'll tell you where it went. right into the ground, six feet deep. six minutes and 20 seconds with an ar15 and my friend, carmen, would never complain to me about piano practice. aaron feis would never call keira miss sunshine. alex schachter would never walk into school with his brother, ryan. scott beigel would neverjoke around with cameron at camp. helena ramsay would never hang out after school with max. gina montalto would never wave to herfriend, liam, at lunch. joaquin oliver would never play basketball with sam or dylan. alaina petty would never... cara loughran would never... chris hixson would never... luke hoyer would never... martin duque would never... peter wang would never... alyssa alhadeff would never...

jamie guttenberg would never... meadow pollack would never... after holding her silence, staring directly at the crowd, for a full six minutes and 20 seconds, she had this message for the students: alarm bleeps. since the time that i, came out here. q rifle, blend in with the students as they escape and walk free for an hour before arrest. fight for your lives before it's someone else‘s job. including the background to the school shooting in florida, which is at the centre of today's rallies. just go to bbc.com/news.

a senior official in egypt has survived an assassination attempt in alexandria. the city's head of security is understood to have been the target of this car bomb. he survived unharmed, but two police officers were killed. this is the street where the explosion took place. as you can see, the whole area is cordoned off and the scale of the damage is quite big, actually. many of the cars here are severely damaged. we understand that an improvised explosive device has been planted under one of the parked cars and it went off when the convoy of alexandria's security chief was passing by. the security chief survived, but we know there are victims among his police guards. the timing of the explosion is quite critical, actually.

it comes two days or less before egyptians go to the polls to choose a new president. the minister of the interior was here a short while ago and he had a careful look at the place. the ministry of interior issued a statement as well saying the security chief is back to work and he will not be discouraged by the explosion. we do not know yet who carried out this attack but we understand that the routes in and out of alexandria are being closely monitored by police forces. the ministry of interior have said that security forces are on high alert but what happened here on this street shows there are still some security loopholes.

the gendarmerie said arnaud beltrame‘s death was a reminder of their daily commitment to protect the people. for the people themselves, his actions are a defiant response to the country's would—be attackers, a reminder of the best of france. today, the site of so much drama was a chilled and empty crime scene. its car park still littered with the debris of a terrified and desperate flight. inside this building yesterday,

arnaud beltrame offered up his life in place of others'. his mobile phone, secretly connected to colleagues outside, giving the operation a vital edge. his brother told french radio that arnaud had died a hero. translation: what he did was beyond the call of duty. he gave his life for strangers. he must have known that he didn't really have a chance. if that doesn't make him a hero, i don't know what would. his mother said she wasn't surprised at what her son had done. "that's the way he lived and the way he worked," she said. "he used to tell me he was just doing hisjob, nothing more." that's not how it feels today. lucy williamson, bbc news, carcassonne. let's return now to the events surrounding the poisoning of the former russian spy sergei skripal. he and his daughter yulia remain critically ill in hospital,

after being exposed to a nerve agent in the english city of salisbury. the uk has accused russia of being responsible — something the kremlin has angrily denied. we can hear now from a man who says he knew sergei when he was a boy. vladimir timoshkov has told the bbc that the former double agent contacted him out of the blue, and told him he'd written to president putin, asking for complete forgiveness. here's his story. stay with us on bbc world news, still to come: turning off the lights. cities around the world do their bit for the annual earth hour to raise awareness about climate change. let there be no more war or bloodshed between arabs and israelis. applause. i'm so proud of both of you.

with great regret, the committee have decided that south africa be excluded from the 1970 competition. singing. streaking across the sky, the white—hot wreckage drew gasps from onlookers in fiji. this is bbc world news today. the latest headlines: hundreds of thousands of young

americans have joined rallies across the united states in support of stricter gun controls. they called on politicians who refused to support a ban on assault rifles to be voted out of office. there's a big story in the world of cricket. let's go to hugh woozencroft with all the sport. major scandal developing in cricket. australia's cameron bancroft is caught ball tampering with his captain, steve smith, admitting that he knew. he knew in advance. the umpire spoke to cameron bancroft regarding an object he appeared to ta ke regarding an object he appeared to take out of his pocket before shining the ball. he was seen putting that object down the front of his trousers. he says he will deal with the damage that comes to his reputation as a consequence.”

saw an opportunity to get some granules from the rough patches on the wicket and tried to, i guess, change the ball condition. —— try to. it didn't work. the umpires didn't change the ball. but once i was cited on screens and having done that, i panicked quite a lot. that obviously resulted in me shoving it down my trousers. i'm not proud of what has happened. you know, it's not within the spirit of the game. my integrity, the team's integrity, we spoke about it, we thought it was a possible way to get an advantage. and obviously it did not work, the umpires did not see a change... change the way the ball was behaving or anything like that. it was a poor choice. we are deeply regrettable, i guess, our actions.

lewis hamilton has described his pole position ahead of formula i's season—opening australian grand prix as the perfect lap. the four time world champion had been neck and neck with his rivals going into the final qualifying session but he finished more than half a second clear in the end with the ferraris of kimi raikkonen and sebastian vettel in second and third. hamilton's mercedes team—mate va ltteri bottas hamilton's mercedes team—mate valtteri bottas crashed and will star near the back of the grid as a result. a shot at the miami open tennis tournament. simona halep, women's world number one, knocked out in the third round beaten by the polish player. top seed roger federer is currently on court against australia's player. one set each. the annual university boat races have been road on the river thames in london. it was a great day

for cambridge, defeating oxford to win the men's, women's and both reserve ra ces , win the men's, women's and both reserve races, the first time that has happened in 21 years. john watson was by the banks of the river. under overcast skies a battle for clea rwater. river. under overcast skies a battle for clearwater. cambridge soon had the pick of it. calm waters and calm heads, building a lead they would never relinquish. cambridge seem to be entering perhaps a period of dominance. four members of this crew powered cambridge to a course record this year. their return ushering in an era of light blue dominance with back—to—back wins for the first time ini9 back—to—back wins for the first time in 19 years. after defeat to oxford last year, can the cambridge crew in the men's race match that performance? they started as strongly and with the lead comes the advantage of plotting the best course. the men's crew demonstrating power and control as they seized the lead. with the tallest man to

compete in the boat race, cambridge's jim m, six compete in the boat race, cambridge'sjim m, six foot ten, kept them there. cambridge take the 2018 men's boat race. an emphatic victory and today, this stretch of the thames belonged entirely to cambridge. just before i go, time to tell you that you can get the latest from the world matchplay golf slash sport. thank you. cities around the world have been marking earth hour — when people are asked by environmental groups to come together to make a contribution to tackling climate change. one of the ways that's being done is by asking people and cities to simply turn out their lights for an hour, to save power and reduce energy usage. this was the scene in taipei in taiwan, where tower 101 led the way, by switching into darkness. in sydney, the city's iconic buildings around the harbour also went dark. you can stilljust about see the opera house

and the harbour bridge — though not everyone in that part of australia joined in. and in manila in the philippines, this group of star wars fans took a different approach — wandering around the city's commercial district using only the illumination from their light sabres. in paris, it was the eiffel tower which slowly went dark, from the top to the bottom. other cities will be taking part once night falls, and we'll bring you the best pictures once we have them, here on bbc world news. the democratic republic of congo has announced that it will not attend a donor conference in geneva next month. the meeting aims to raise nearly two billion dollars for what the united nations has described as a catastrophic humanitarian crisis. the prime ministerjose makila said the un's decision to declare a top—level emergency in the drc was stalling development and discouraging investors. with more, here's david campanale. safety of a kind for refugees

fleeing inept upsurge of violence in the democratic republic of congo. to get in neighbouring uganda, these people first had to take the treacherous route across the a0 kilometre wide lake alberta. translation: we left the homes because we were suffering. some people left our houses but we stayed behind without our husbands. some people lost their husbands because they were chopped with machetes. others lost their children and so many have been left orphaned. according to the united nations, the country is in a top level emergency. more than 680,000 congolese refugees are now inside uganda or nearby burundi. another a.5 million people

are internally displaced. the crisis is, in part, driven bya are internally displaced. the crisis is, in part, driven by a breakdown of government authority. this man says the problem requires an end to the presidency ofjose makila who refused to leave power at the end of his mandate in 2016. the un says humanitarian aid is needed by over 13 million people. with underfunding the single biggest issue. translation: what we are saying is that not the children are at risk of dying, it's that they are dying. we have visited the hospitals, we see in the villages, and thousands of children have died because of this malnutrition which is acutely severe. not enough attention given to this situation. a donor conference for the drc has been called next month in geneva with the aim of raising $1.7 billion, four

times what the un secured last year. but the government of presidentjose makila has told the united nations it will not be attending. with his prime minister accusing the iwan and ola agencies of giving the country a bad name and the discouraging investors. —— accusing the un and other agencies. with this wealth of resources has come multiple conflicts, corruption and a political crisis. elections are scheduled for the end of this year but its as yet unclear if president jose makila give way. a reminder of our top story: hundreds of thousands of young americans havejoined rallies across the united states in support of stricter gun controls. while the biggest anti—gun rally in a generation was taking place in washington — similar marches were happening in us cities from coast to coast. demonstrators called on politicians who refused to support a ban on assault rifles to be voted out of office. i can't imagine how scared they were when someone came

to their school with a gun. it's crazy, so they're brave enough to go through that. to the parkland students, i think they are so brave and so courageous for doing this. i'm so sorry for what they had to go through and i promise to make a change for them and every kid everywhere. it's not the people that have the guns, it's the guns themselves and they need to stop it. adding more guns into schools is not going to do anything at all. it's going to make the matter even worse and it's going to be counter—productive. some of the people taking part in those rallies across america. plenty more on our website. thank you for watching. a battle between mild air and cold

air. the sunshine one out across much of scotla nd the sunshine one out across much of scotland and northern ireland. a gorgeous spring day in the borders earlier on. at least it was dry for a time. unlike further south. both outbreaks of rain. this is storm hugo. a torrid night across spain and southern france. throwing up the cloud across england and wales. producing some outbreaks of rain. clearer skies will eventually win out as it works its way south. clearer conditions have pushed to all but east anglia in the south—east. showers across scotland and northern ireland, icy conditions with rural parts dropping below freezing. 7 degrees in the south—east corner, the cloud will hang into the morning. there may be a great start east anglia and the south—east but it will brighten up.

ba rdsley south—east but it will brighten up. bardsley improved south—east but it will brighten up. ba rdsley improved day south—east but it will brighten up. bardsley improved day for most on sunday. good, long, sunny spells —— vastly improved. sunshine ever had. some showers in the north. a mixture of rain, hailand some showers in the north. a mixture of rain, hail and hill some showers in the north. a mixture of rain, hailand hill sleet some showers in the north. a mixture of rain, hail and hill sleet but evenin of rain, hail and hill sleet but even in the sunshine, temperatures into double figures. clearer conditions into sunday evening. only one thing that will happen, temperatures dropping widely. frost will develop for just about all on monday morning. a few towns and cities will stay just above freezing. elsewhere, it scrape your cars. it will be a battle. some milderair cars. it will be a battle. some milder air pushing through to start with and then it will be a case of what will win, the atlantic winds or cold air trying to make this comeback from scandinavia ? cold air trying to make this comeback from scandinavia? on monday, after a frosty start, the atla ntic monday, after a frosty start, the atlantic air will win. a sunny start, mist and fog in central eastern areas, cloud amounts will increase. many will stay dry but the

west will see rain before the end of the day and the breeze will pick up. temperatures still in double figures. monday night, this area of low pressure will work across bringing rainfor low pressure will work across bringing rain for many. south, it will start to introduce colder air and snow in hills in northern england and scotland. as british summertime begins and the clocks go forward tonight, cold air will make a comeback. this is bbc world news. our top stories: hundreds of thousands of people have taken to the streets to cool for stricter gun control laws in america. tributes were led to survivors of the florida school shooting. the captain of the australian cricket team has admitted to ball tampering in the first test against south africa after a team—mate cameron bancroft was caught in the act by tv cameras and he said was a big mistake but he wouldn't stand down. a senior official in egypt's survived an assassination attempt in alexandria. the city's head of security is

understood to have been the target ofa car understood to have been the target of a car bomb. he survived unharmed but two police officers were killed. france will organise a national tribute for the police others