welcome to bbc news — i'm mike embley. our top stories. rising tensions in the middle east — iran denies claims by washington that it carried out attacks on two oil tankers in the gulf. it is the assessment of the united states government that the islamic republic of iran is responsible for the attacks that occurred in the gulf of oman today. after a controversial and difficult two years, sarah sanders confirms she's quitting the white house in a few weeks. a special report from sudan — as military rulers admit their orders led to the deaths of more than 100 protestors. and some of the oldest trees

in the world are dying — researchers in yosemite national park are trying to understand why. hello: the us secretary of state has accused iran of being behind attacks on two tankers off its coast in the gulf of oman — one of the world's busiest oil export routes. both crews were rescued after explosions on board. tensions are already high in the region, and the incident has pushed up oil prices. the leadership in tehran has denied any involvement, saying others are trying to ruin the country's diplomatic relationships. here's our chief international correspondent, lyse doucet. this morning in the gulf, a first oil tanker set ablaze, ignited by an explosion. crew members on this norwegian vessel were rescued by a passing cargo ship. these scenes filmed by iran's navy.

an hour later, another tanker, japanese owned, also hit by an explosion. it's still not clear what caused these latest attacks in one of the world's busiest shipping lanes. today in washington, unequivocal condemnation of iran. these unprovoked attacks present a clear threat to international peace and security, a blatant assault on the freedom of navigation and an unacceptable campaign of escalating tension by iran. the attacks took place close to the strategic strait of hormuz, vital to world trade, where tensions have been mounting for months between regional rivals. on one side there are arab states including key us allies in the gulf. on the other side is iran. at its narrowest point, the strait of hormuz is just 21 miles wide, and there are two lanes for tankers to pass in opposite directions. a fifth of the world's oil exports, almost 19 million barrels a day, passes through. so attacks on tankers can threaten oil supplies, drive up prices and fuel the tensions many worry could tumble towards war. this was meant to be a week of diplomacy. japan's prime minister,

shinzo abe, is in tehran, hoping to help ease tensions, only to see them escalate. today he met iran's top leader, ayatollah khamenei. iran calls the timing of these attacks are suspicious, and reject any responsibility. iran is also blamed for this. an attack yesterday on an airport in saudi arabia, 26 injured. yemen's houthi rebels, aligned to iran, say this was their work. two weeks ago, king salman called arab and muslim leaders to mecca, islam's holiest site, urging them to condemn iran. saudi officials told me then they don't want a war, but some sources spoke

of a proportionate response. so what's next? last month the us moved an aircraft carrier and bombers to the gulf. president trump says he wants to talk to iran. they won't, not while he imposes crippling economic sanctions. everyone says they don't want a war, but everyone is on edge. lyse doucet, bbc news. in the past hour or so the pentagon has released video which us central command says shows the crew of an iranian patrol boat removing an unexploded limpet mine from the hull of a japanese—owned tanker. and you can keep up to date with the latest on this story on our website. you'll also find a feature on the history of the tensions between the us and iran — that's all at bbc.com/news or download the bbc news app. let's get some of the day's other news.

the man accused of carrying out the terror attacks in christchurch, new zealand has pleaded not guilty to all 92 charges against him. brenton harrison tarrant appeared by video link at the high court. he's denied 51 charges of murder, a0 charges of attempted murder and one charge of terrorism. the ukrainian captain of the cruise ship that collided with a tourist boat on the river danube, killing 28 people, has been released from police custody. he paid $50,000 bail, and promised to remain in hungary until investigations are complete. the world health organization has called an emergency meeting in response to the news that ebola has spread to uganda from eastern congo. the meeting will decide whether the outbreak amounts to a public health threat of international concern. the current ebola epidemic began in august last year in eastern congo and has already infected over 2,000

people, killing two thirds of them. the race to lead the conservative party in the uk — and become the next prime minister — has been cut to seven people in the first round of voting. borisjohnson, former foreign secretary and mayor of london, has a strong lead with 114 votes — that's more than a third of conservative members of parliament. jeremy hunt emerged as his closest rival with just 43 votes. the british home secretary has approved an extradition request from the us forjulian assange. the wikileaks co—founder — who's wanted for the mass release of american state secrets — is currently serving a 50—week sentence for skipping bail and fleeing to the ecuadorian embassy in london in 2012. president trump's white house spokesperson, sarah sanders will leave herjob at the end of this month. in a tweet, he praised her as "a warrior" . "a very, very fine woman." she once said god wanted donald trump to become president.

the bbc‘s chris buckler in washington has more on sarah sanders leaving the white house, and one other person definitely staying. yeah, let's talk about the person who is going and that is sarah sanders. as you know it is a prestigious position to become the press secretary for any president, but it is not an easyjob and i think that is true under president trump who can be outspoken and it is part of thejob, part of the role to stand there and to defend the words of the president, no matter what he says. and certainly sarah sanders at times has struggled with that when she was asked whether or not the press are the enemy of the people or whether or not some of the things he said about individuals are appropriate. she also struggled, for example, whenever some of his family separation policies that she felt strongly about, but she had to stand and take the president's line time and time again. it's also put her under criticism at times because she is so close to the president and seen as close to the president. perhaps most famously at the white house correspondents dinner when the comedian michelle wolf made some jokes that many people felt were perhaps not of the best taste.

spoke about her appearance, for example. sarah sanders is from a political family. her father was mike huckabee who was at one stage the governor of arkansas so she knows about the rough—and—tumble and she said today she was so honoured to have served the president. she wants to spend more time with her children going forward. the president did make a suggestion that perhaps she may wish to be the governor of arkansas going forward. in the meantime she says she will simply be a loyal and outspoken supporter of president trump. as for the person who is staying, that is kellyanne conway who has been criticised by a government watchdog known as the office of the special counsel. it keeps watch on government employees and has what is known as the hatch act in mind. a set of ethical rules for government employees that say they should remain non—partisan. they cannot show political favour to one party or the other. it describes kellyanne conway, an advisor to president trump, as a repeat offender of the hatch act.

on occasion she has supported individual republicans and has criticised democrats forcefully. the white house says as far as it is concerned, this is a chilling attempt to attack free—speech and although kellyanne conway has not commented today, in the past she has used these words. "blah, blah, blah. "if you are trying to silence me through the hatch act, "it will not work." and given that president trump is the one who enforces it, i don't think it will amount to much and kellyanne will definitely be staying. sudan's military rulers have admitted they ordered the operation that led to the killing of at least a hundred peaceful protesters more than a week ago. the un security council has condemned the massacre and called for an end to attacks on civilians.

the protesters were demanding a swift transition to civilian rule. our africa editor fergal keane — in the capital khartoum — has been talking to some of those who witnessed the atrocity at first hand. the massacre had one aim — break the revolution by traumatising its supporters. the rapid support force militia was unleashed on peaceful protesters. in the weeks before, i'd seen how thousands believed that peaceful protest could end decades of military rule. everybody‘s chanting, everybody just feels the sense of freedom. they have never felt before. and i feel i am very empowered. it's the sudan that i wanted to have.

but in the dawn hours ofjune the 3rd, freedom was stolen. now for the first time, some who witnessed the worst of the brutality are speaking. translation: there was a huge number of these soldiers, and there was very intense shooting. people who were getting shot and falling. along with the shooting, there were people around us who were hitting us with sticks and whips and things, so we weren't able to carry all the people who were shot. ahmed was shot himself as he ran. wasab al tahir was badly beaten when militia attacked a clinic. only the intervention of the regular army saved his life. translation: i was beaten all over my body until i passed out. all the people with me had serious injuries. one of them was a doctor with broken ribs and arm. he was also hit on the head.

at that point, they had already cocked their weapons, and were ready to shoot us inside the clinic. the army officers took them outside. if they hadn't arrived, we would have been executed. after the killings, the round—ups began. the massacre scattered the opposition, but there are activists hiding out all over the city. we are on our way now to meet some of them at a safe house. these witnesses asked for their identities to be protected. the man on the bed was shot, and on his way to hospital when the militia stopped the ambulance. translation: there was another patient lying next to me. his stomach was open from one side to the other, and some of his organs were outside. one of the people with me said to them, this guy's stomach is open, his intestines are out. he could die. they said, "let him die." then they hit the female doctor with a stick. the militia are also accused of rape. an ambulance driver witnessed

the attack on what appeared to be a wounded woman being helped by an activist. translation: they were feeling her up. they were arguing over who gets her. each one of them wanted to take her off the shoulder of our brother. what's important is that they took her and they did what they did. at the end, we found out that the girl had been dead from the start, but they still didn't let her be. i told you i cannot describe 1% of what i saw. death in all its forms, ugliness of all kinds. the details... he sobs. the regime tonight denied any rapes took place, but it is refusing to allow

an international investigation. it's left the revolution in trauma. even women older than me, could be 50 or 60, they made them lie on the road and they beat them up. you saw this? yes, i saw this, and then i stopped looking out the window. ifeel guilty, actually, because i'm safe. this sudan of protest has been driven underground, but all i've met in the last few days still believe in peaceful change. after what's happened, that feels remarkable. fergal keane, bbc news, khartoum. and just a footnote here, sudan's former president, omar al—bashir, has been charged with corruption. after three decades of authoritarian rule, he was overthrown and arrested in april. stay with us on bbc news, still to come: the ten—year project to save the trees of yosemite, some of the oldest and tallest in the world.

the day the british liberated the falklands. and by tonight, british troops had begun the task of disarming the enemy. in the heart of the west german capital, this was gorby—mania at its height. the crowd packed to see the man who for them, has raised great hopes for an end to the division of europe. michaeljackson was not guilty on all charges. the screams of the crowd, a testament to his popularity and their faith in his innocence. as long as they'll pay to go see me, i'll get out there and kick 'em down the hill. what does it feel like to be the first man to go across the channel by your own power? it feels pretty neat. feels marvellous, really.

welcome back. good to have you with us. the latest headlines: iran denies it but the united states and the uk say they blame tehran for the attacks on two oil tankers. after a controversial and difficult two years, one of donald trump's closest allies sarah sanders confirms she's quitting the white house in a few weeks. let's return to our main story now: the us accusing iran for the oil tank attack — which iran denies. so who is responsible? here's the middle east analyst ryan bohl, from stratfor intelligence. it stems from the fact that we have not seen the intelligence come out publicly from the agencies like the americans and british, who was saying it was the iranians. we have their assertions but we don't have their assertions but we don't have the photographs or videos they say exist. that is creating the

ambiguity that whoever was carrying out these attacks was counting on. it would be a slightly odd thing for iran to do to attack a shipment of oil heading forjapan at a time when the japanese prime minister is in tehran for his first visit in decades. the thing that seems most likely for their motivation is that they chose this time to send a strong message that thing smith and by their asymmetric capabilities. there is confusion about the actual probability of the iranian government. attacking the japanese tankers while the japanese prime minister was in tehran may or may not be linked. it is not clear at the moment. it is clear is that the iranians were sending a strong message through this and that seems to have been received. are you at all doubtful about the official american line. john bolton, the us national security advisor, is on

record from sometime ago saying he favours war with iran. and it was the us that walked away with the agreement that limited iran's nuclear programme at a time when other high—powered thought iran was sticking to it. since then the us has been threatening iran. there has been a lot of rhetoric. rhetoric suggest that there are a couple of stories coming up from the white house, one is that there is a difference between bolton and president trump who is in favour of renegotiating the iranian deal but a lwa ys renegotiating the iranian deal but always keeps the options open. we have a division within there. with that being said, the idea that the americans are pushing a narrative thatis americans are pushing a narrative that is their own purposes without, perhaps, having the full story, that is not an unreasonable thing was to be suspecting right now. but when we look through the region and we started to say to ourselves who was could have pulled this off, who was asa could have pulled this off, who was as a motive at this particular moment? most of the other actors kinda fall off the list. it was close to a ride, it was carried out

with means we know the iranians have. and it was carried out in a way that was specifically tailored to ensure that there would be no immediate american retaliation on iranian targets. the americans may decide to escalate sanctions further and employ more forces, but right now with this ambiguity we don't have to move greatly in. that leads us have to move greatly in. that leads us to the idea that the iranians we re us to the idea that the iranians were using this to send a message without quite giving the americans a cause they definitely gain something by giving them to think about. after days of protests in hong kong, a pause, the extradition bill. 81 people have been injured, 11 arrested. most visible reminders of the protests are gone, but the atmosphere is still tense. the bbc‘s sharanjit leyl is there. what a difference a day makes. we we re what a difference a day makes. we were right here at this by 2a hours ago when the streets could not have looked more different. there was rubbish piled high across the streets are being left over by the

thousands of protesters who had blockaded these streets to prevent lawmakers from entering the legislative council complex just there to debate this controversial extradition bill. as you can see now, this friday, the traffic is moving, the streets are cleared of the rubbish. but if you take a look closer, look at this. these are barricades quite literally being forced from the pavement, just a sign of the share numbers of protesters who were here, of course, protesting on wednesday. and, of course, there is still a sense of shock here in hong kong at there was level of violence the city has seen for decades. you know, police firing rubber bullets, using tear—gas against protesters, and a number of arrests have been made against what the authorities and the territory's leader has said is organise writing. they have spoken to students as well is they feel a sense of frustration, rage, disappointment that the

government forfailing rage, disappointment that the government for failing to back down over this controversial bill and there are more protests planned for sunday, a week after there were a million people on the streets, organisers say, and emotions will continue to run high. sharanjit leyl, bbc news, hong kong. an ancient tower in afghanistan has collapsed, the government's ability to protect the country's artefacts. footage posted online shows a fort in the old city of ghazni crumbling — the tower was among dozens already destroyed in the city. the fort once had 32 towers. officials blame heavy rain, some others accuse the government of negligence. ghazni's islamic and pre—islamic architecture is widely admired although years of war have taken their toll. the city has been designated an asian city of islamic culture.

talking of things old and tall. 10 years ago researchers in california launched a long—term project to track the life histories of some of the world's oldest trees. they wanted to find out why some of the giant species in yosemite national park are dying out. the first decade has already seen dramatic changes, as peter bowes reports. this is yosemite national park, a vast expanse of forest land and some really breathtaking views. when i came here ten years ago i met with a group of scientists just embarking on a long—term project to track the life histories of these trees, some of the oldest and tallest in the world. we have understood from previous research that the number of large diameter trees is less than it used to be. what we would like to do is investigate why that is. i've come back to see how things have changed. it's right down there, isn't it? just a kilometre away are the 35,000 trees. shall we go have a look? let's do it. let's go. the tree right over there is the same tree that we filmed. so, here we can see the tag. the same tag, it was fresh ten

years ago and we can see the discolouration by the heat of the fire. the park embraces science and the role of fire to manage the forest year round. five years into the project, in 2013, we experienced a fire. a backfire that the national park service lit to check the advance of the rim—fire, at the time the largest fire in the sierra nevada of california. today my role is to remeasure all of the trees that are alive, to compare it to the measurements we took after the fire. 0.24 metres. the year after the fire, my first year here, a lot of the trees died, especially the small ones as a direct result of the fire. now, we are starting to see some more delayed fire effects. the fire did not immediately kill any of the larger trees.

following the fire we had two very, very strong drought years — very, very dry. we had a beetle outbreak of several species of beetles, which successfully killed a lot of the trees, and it's really this combination of factors that provide a situation that the trees can't resist well. even in the ten years we have already been studying, we still don't know enough to track the reasons why those rates of tree deaths might be changing. we are just starting to be able to understand drought effects. we're just starting to understand how the beetles kill trees in patches. we've had very promising early results but it's still an ongoing process. if you were to come in and look at things for a couple of years, you really wouldn't be able to get the whole picture. our goal is nothing less than to understand how this forest works. this long—term science project is still in its infancy. the researchers plan to return as long as they are able, gradually handing over the study to the forest ecologists of the future. peter bowes, bbc news,

in yosemite national park. just briefly, cuba gooding junior has handed himself into new york police to face a charge of forcible touching. a woman claimed the actor grabbed her breast at a bar in manhattan on sunday evening. he denies the allegation. and the remainder of that manias again, the pentagon has released video which us central command claims shows the crew of an iranian patrol boat removing an unexploded limpet mine from the holiday japanese own tanker. the secretary of state of the us has accused iran of carrying out two attacks on tankers in the gulf of oman, one of the well‘s busiest export roots. iran denies that. there is more on that and all the news any time on the bbc

website. and you can get in touch with me and most of the team i'm @bbcmikeembley. thank you for watching. hello. as the flooding and disruption continues, particularly across parts of england, some spots have had three months' worth ofjune rainfall and just a week, over 150 millimetres in the wettest places. still rain in the forecast but not necessarily the same areas, as low pressure adopts a new position to the north—west of the uk in the coming days, means showers are most frequent in the north and the west. and there is, as friday starts, a fresh area of rain affecting parts of england and wales, also rain in north—west scotland. fairly chilly for the clearer parts of scotland and northern ireland as the day begins. but where you start the day with rain, things should improve as we go through the day, it should brighten up and it will be an afternoon of sunshine and showers. here's a look at things at 8:00 in the morning. so you're in the rain in north—west scotland, especially into the western isles, one or two showers elsewhere, but where you have got the clear skies and here into northern ireland, too, your temperature could be around

the mid single figures as the day first starts. but you can see the outbreaks of rain from northern england, the midlands into wales, perhaps affecting parts of south—west england, perhaps the odd showery burst towards the south—east. but the further south—east you are, may well be seeing some sunshine as the day begins. so on through the day then, you can pick out the two areas of rainfall but they are slowly easing and things start to brighten up. more widely so by the afternoon, it is sunshine, showers, may be heavy and thundery, very few for east anglia and south—east england, perhaps up to 20 celsius here. for most of us here it will feel a bit warmer, especially where you've had days stuck in the rain. going through friday evening, we'll see another area of rain, this time pushing into northern ireland, and then feeding on towards south—west scotland, wales and western england as saturday starts. ahead of that, it will be mainly clear bar the odd shower. that takes us on to the weekend, the big picture has low pressure here to the north—west of us, it will be feeding in weather disturbances from the west this time, and this is the first one we are contending with on saturday morning. so it will be an area of cloud, some showery rain out of that, slowly moving further east as the day goes on. ahead of it, sunny spells, maybe a shower. behind it, sunny spells

and the chance of catching a shower. on a fairly breezy day with temperatures topping out in the mid to high teens. now, part two of the weekend on sunday, if anything, it looks a little bit breezier, and it will be another day of sunshine and showers. now the showers most frequent in the north and west where again it could be heavy and possibly thundery, some though, will push a little bit further east on the breeze during the day. showers — not everybody will catch one. and again, temperatures mostly in the mid—to high teens. that's your latest forecast. i'll see you soon.

this is bbc news, the headlines: the us and uk have accused iran of attacking two tankers off its coast in the gulf of oman — one of the world's busiest oil export routes. tensions are already high in the region, and the incident has pushed up oil prices. the leadership in tehran has denied any involvement, and accused the us of trying to sabotage international diplomacy. in the past hour the pentagon has released video which us central command says shows the crew of an iranian patrol boat removing an unexploded limpet mine from the hull of a japanese—owned tanker. sudan's military rulers have admitted they ordered the operation that led to the killing of at least a hundred peaceful protestors 10 days ago. they were demanding a swift transition to civilian rule. the un security council has condemned the massacre and called for an end to all attacks on civilians.