this is bbc world news today. i'm martin stanford. our top stories: there has been international condemnation after saudi arabia admits the missing journalist jamal khashoggi was killed in its consulate. thousands of people travelling across central america to the us are now stranded on mexico's southern border. hundrends of thousands of protesters march through london demanding a referendum on the government's final brexit deal. and two satellites developed in europe and japan leave earth for a seven—year journey to the planet mercury. hello and welcome to bbc world news. turkey says it will reveal all details about the killing of journalist jamal khashoggi, after saudi arabia admitted for the first time he had been killed in its consulate in istanbul.

state television reported that he died in a fight. turkish officials previously said he had been deliberately killed. our diplomatic affairs correspondent james robbins reports. after 2.5 weeks of denial, saudi arabia is changing its story. state tv announced the admission that jamal khashoggi was killed by its officials. translation: the discussions that took place between him and the individuals that met with him during his presence in the saudi consulate in istanbul led to an argument and fist fight with jamal khashoggi, which led to his death. that is also the admission of a big saudi lie — previous insistence that the journalist didn't just walk into the consulate, he left safely too. many believe the killing could only have happened with the permission

of saudi crown prince mohammad bin salman, and that the new story of a fight rather than premeditated murder is designed to shield him. president trump, who has been torn between criticising the saudis and protecting business with them, first seemed willing to accept the new saudi explanation as credible, but now seems less willing. they've arrested a large number of people having to do with what took place at the consulate. it's a big first step. it's only a first step but it's a big first step. do you consider it credible, their explanation? i do, i do. but many disagree, including within his own republican party. senator lindsey graham said... so will the saudi admissions and arrests solve britain's dilemma

— how to respond? hardly. the government is committed to uphold a world order based on rules, but it doesn't want to inflict too much damage on saudi partnerships it values enormously. the foreign office confined initial reaction to a short statement. it begins... but don't expect action before turkey publishes some of its evidence. turkish officials have suggested a grotesque sequence of torture and killing inside the saudi consulate. turkey is promising to reveal all its findings. james robbins, bbc news. earlier borzou daragahi, an international correspondent for the independent, told me what he thought about the saudi admission. there are many questions that are left u na nswered. there are many questions that are left unanswered. at this point, the saudis have made their case. it

seems like some elements in the trump administration have accepted it. others are sceptical. what really counts now is how the turkish government will react. they have all the evidence, they are continuing their investigation. they have not made any announcement yet, and all indications are that the turkish government finds the sound the explanation insufficient and that they are going to come up with more information on more details of the investigation in the coming days —— saudi explanation. what are the ramifications, do you think, for saudi arabia in the near—term, the germans are already talking about curtailing arms sales, for instance? well, i think that beyond those sort of business deals, i think that many of business deals, i think that many of them will remain. i think it will sort of suggest a weakening of the crown prince, mohammad bin salman. he has been very badly damaged by this. whether he hangs on as crown prince, is a good question. it does look like he will remain in his

office. but there is a serious attempt not just office. but there is a serious attempt notjust on the part of dissidents and activists and so on to wea ke n dissidents and activists and so on to weaken him, but also on the part of very powerful members of the royal family, who feel sidelined by him. in addition, he has a very powerful adversary in the turkish president, erdogan, who opposes mohammad bin salman but wants to maintain good relations with saudi arabia, and seems to be offering the saudis a deal. he will not push this investigation, in exchange for a weakening or sidelining of mohammad bin salman. and a personal tragedy in this forjamal khashoggi is that he thought turkey was a safe place. by he thought turkey was a safe place. by all accounts he was thinking about setting up a new life there with his fiancee. indeed, reports are that he had purchased an apartment here in istanbul. istanbul right now is a sort of haven for arab politics and culture. many

people from the sort of aftermath of the arab spring uprisings had to leave their countries wound up in this city, and he thought that this would be a good place for him to continue to kind of state engaged in middle east politics and affairs while maintaining a foothold in the west with his residence in washington, and his column in the washington, and his column in the washington post. which begs the question, what next for erdogan what is his next move, do you think? i think they will continue the investigation, i think they will continue possibly leaking information from the investigation. one crucial question that o'brien has on their mind if the tapes, these tapes that supposedly exist that record the final moments of jamal khashoggi. will turkey ever release those tapes, and what effect will they have if they are released? and i think that is one thing that if they exist, he is definitely

holding over the saudis. hundreds of central american migrants have used rafts and boats to cross the river marking the border between guatemala and mexico in an attempt to continue theirjourney to the united states. thousands of people were left stranded on the frontier bridge after mexican police stopped them entering the country on friday. the bbc‘s ana gabriela rojas is on the bridge on the mexican side of the border, and she joins us live now. has the situation changed at all, are they letting anyone through? yes, the situation has evolved a lot in the last couple of hours. actually, some groups of migrants we re actually, some groups of migrants were already tired of waiting on the line on the border with mexico, so they just went themselves from guatemala to mexico, so they crossed by the river. there were some scenes of panic, because some people were drowning, some people didn't know

how to swim. the river has a lot of current these days. but finally, hundreds, we don't know how many, but more than 1000, for sure, ifeel in this part, tried to organise what is the next step for this part of the caravan, that now is separated. one part is still waiting on the bridge to pass through the authorities and the other part is here, organising to see will they continue. they are saying so far they might continue walking towards they might continue walking towards the us. i mean, that is their intent, isn't it, to try and get into the usa. what are the mexican authorities doing? are they going to let them into the park, but no further? we still don't know. they haven't said anything yet, but it looks like they can't do much, because it is so many people together. so we are still waiting to see what the authorities are going to do, but so far they are just here. there is a station just in

front of me, and it seems safe for them so far. and the migrants turning to some ingenious means of getting across the water, isn't it? we have seen people and they are using a rope to guide them, they seem to be commandeering boats to get across. almost anything to get across that river. yes, it was a lot of people crossing, so at the beginning they put a line across the river, and some of the stronger ones, the young man, were walking towards the river. some of them were able to swim. it is not very... it is not to... it is shallow, but it has a lot of current, as i said before. and some of them were in boats. but the boats, some of them we re boats. but the boats, some of them were not allowed. the police have threatened them not to take migrants, so that is the situation. and what is the situation in terms of how many people are left? is that bridge still full of more people?

sorry, i didn't get it. the pictures we saw earlier today of the mass of people occupying the bridge, sitting down, resting awhile, are there still more migrants waiting to cross the border? yes, they are still there. the ones who went to the authorities, they are still there. but the news is that more migrants arrived today. but some of the people are even starting now from honduras to come here. so the ca rava n honduras to come here. so the caravan is just becoming honduras to come here. so the caravan isjust becoming bigger and bigger, more people are willing to travel now that they know that so many people are on the move. thank you very much. several million afghans have voted in parliamentary elections, the first to be organised entirely by the government since 2001. polling stations which could not open on saturday plan to do so on sunday. but the elections have been marred by violence, as sekunder kermani reports from kabul. the taliban told them

to stay at home. instead, afghans began queueing outside polling stations even before they had opened, with thousands of soldiers deployed across the country. 15 people were killed in a suicide bombing in kabul. and there were dozens of similar incidents. but through the day, voting did go ahead. translation: of course everyone is scared, because security is bad. but, despite all those fears, we are here and voting anyway, because our destiny depends on it. translation: i hope the people who are elected will do something for the young generation, and to improve security

for the country. inside polling stations, women and men voted in separate sections. almost 9 million people have registered to vote for more than 2,500 candidates. despite the threat of violence, people here in kabul are turning out to vote, determined to have a say in how the country is run. but, across afghanistan, nearly a third of all polling stations are closed because of security concerns. in a country where politicians are often seen as corrupt and linked to ethnic tensions, there is a degree of optimism about some of the new candidates standing, many of whom are young and from professional backgrounds. that is why the taliban are afraid. previous elections in afghanistan have been marred by allegations of fraud. many fear that will happen again, despite new biometric devices meant to prevent anyone voting more than once. today's election is a key test of afghanistan's security forces,

ahead of next year's more politically significant presidential elections. it has been a day of defiance, but also, as it often is in afghanistan, of bloodshed. sekunder kermani, bbc news. let's get some of the day's other news: president trump has confirmed that the united states will withdraw from a nuclear agreement with russia. the treaty required both countries to get rid of short and intermediate—range missiles, but washington has accused the kremlin of breeching the deal. russia is accused of developing missiles, which could be used against european nato countries. the brazilian authorities say the federal police will investigate huge amounts of fake news on social media regarding this month's presidential run—off election. it is alleged that supporters of the far—right presidential front—runner, jair bolsonaro, used whatsapp to spread disinformation targeting his left—wing opponent fernando haddad. mr bolsonaro team has denied any wrongdoing. a presidential candidate in georgia has been detained by police for handing out cannabis

joints at a rally. zurab japaridze is running on a libertarian and pro—legalisation platform. he called his actions an act of civil disobedience and demanded the right to legally buy and grow marijuana in the southern caucasus nation. the election will be held on 28 october. stay with us on bbc news. still to come: up, up and away. the ariana rocket carrying two satellites leaves earth on a seven—year mission to mercury. a historic moment that many of his victims have waited for for decades. the former dictator in the dock, older, slimmer, and as he sat down, obedient enough. dawn, and as the sun breaks through the piercing chill of night on the plain outside korem,

it lights up a biblicalfamine, now, in the 20th century. the depressing conclusion — in argentina today, it's actually cheaper to paper your walls with money. we've had controversies in the past with great britain. but as good friends, we have always found a good and lasting solution. concorde bows out in style. after almost three decades in service, an aircraft that has enthralled its many admirers for so long taxis home one last time. this is bbc news. the latest headlines: there's been international condemnation after saudi arabia admits the missing journalist jamal khashoggi was killed in its consulate in istanbul.

president trump is still stressing america's strong bonds with riyadh. thousands of people travelling across central america to the us are now stranded on mexico's southern border. here in the uk, huge crowds have marched in london to demand a referendum on the terms of britain's withdrawal from the european union. organisers from the group called people's vote said 700,000 people took part. pro—leave groups dismissed the protest, saying people had already expressed their will in the brexit referendum. more now from our political correspondent, chris mason. they came from every corner of the uk and beyond. it's a campaign that wants what it calls a people's vote — in other words, another referendum. what do we want? all: people's vote! when do we want it? all: now! there were some political faces you mightjust recognise here, but the vast majority were ordinary people still deeply angry about brexit.

it's all been lies from the start and it needs a second vote. we need a second vote to get us out of this mess! to what extent can today persuade people who voted a different way from you to vote a different way in future, if there was another vote? i'm not sure that today will. it's seeing the politicians making a complete mess of the negotiations that will persuade them. in the first vote, we thought the brexiteers knew what they were doing. now we know they couldn't organise a party in a party shop. i feel really strongly that, you know, people particularly where i'm from in the north didn't vote to lose jobs, didn't vote to close factories, and i think that it's right to make it clear to people that that is the consequence of what they voted for. more than anything, i was born in 1982, i feel more european than i do british, in some ways. so, on a personal level, i feel like my identity is being lost. a noisy walk in the autumn sunshine ended,

for those at the front, at least, in parliament square, where some celebrities... hello, london! ..and politicians from a range of parties addressed the crowd. let the message ring out loudly and clearly today. it's time for this vital issue to be taken out of the hands of politicians in westminster. there's no doubting this is a big march, there's no doubting the passion of those taking part, but their demand for another referendum collides with the government's opposition to one. they hope, though, with politics as turbulent as it is at the moment, anything is possible. good morning, everybody. the march in london wasn't the only brexit—related event today, though. here in harrogate, in north yorkshire, a much smaller gathering, but one of a series from leave campaigners. that's our message — get on with it. fulfil your promises to us. you said if we voted to leave, it would happen. it needs to. and some ukip supporters decided to take their pro—brexit argument

to the anti—brexit march in london. they were not well received. it shows how thick you are — you don't know... it was a reminder, not that it's needed, that the divisions, anger and open hostilities provoked by the referendum have not gone away. chris mason, bbc news at westminster. kidnappers have released one of africa's richest people. tanzanian billionaire mohammed dewji was in captivity for more than a week. it's unclear if a ransom was paid. rhodri davies has more. these are the remnants of a personal and national ordeal. in an upmarket area of dar es salaam, police were searching the scene where africa's youngest billionaire was released. mohammed dewji was set free early morning after ten days of captivity. he was unharmed apart from some bruises on his hands and legs.

mohammed dewji broke the news himself on his company's twitter account, saying: "i thank allah that i have returned home safely. "i thank all my fellow tanzanians and everyone around "the world for their prayers." and while the kidnappers remain at large, they received a warning. translation: our country is safe and will continue to be safe. these people will be punished according to the law. we must bring an end to this. we can't let the kidnappers get away with this or they'll simply try again. dead or alive, we'll be happy either way. these people are our enemies. and in a country with high levels of street crime and poverty, the kidnapping of someone with so many friends stands out. dewji's family were able to offer a $4a0,000 reward for information

leading to his rescue. that's after armed gunmen abducted him at one of the city's hotels as he arrived for a morning work—out. known locally as ‘mo', dewji is said to be worth $5 billion and his companies employ more than 22,000 tanzanians. so, his release has settled an ease for many in the country, even if it's still unclear whether a ransom was paid and what it's still unknown where the kidnappers are. let's take a look at some of the other stories making the news. australia's governing coalition has lost its one—seat parliamentary majority after a by—election in sydney. independent candidate kerryn phelps comfortably won the wentworth seat, which has historically been held by the centre—right liberals. the previous mp was the former prime minister malcolm turnbull, who was ousted by his colleagues in august. the defeat suggests the liberal party will face major challenges in next may's national election. a us lotteryjackpot has reached

the record sum of $1.6 billion after months without a winner. the prize, known as mega millions, has been growing sincejuly. the next chance of drawing the six lucky numbers will be on tuesday. the duke and duchess of sussex have opened the fourth invictus games tournament in sydney as part of their tour of australia and new zealand. prince harry used a speech at the event to talk of his joy at his wife's pregnancy. the games were started by the prince in 2014 and will see injured service personnel from 18 countries compete in 11 sports over eight days. around 100,000 protesters have been demonstrating outside the cuadrilla —— around 1,000 protesters have been demonstrating outside the cuadrilla fracking site in blackpool in the north—west of england. it follows the release of three men who'd beenjailed in connection with a previous protest at the same site. our correspondent judy hobson was there. this rally is right in front of the

tracking site. there are about 1000 people here today. right at the front of the march we have just had we re front of the march we have just had were the three men jailed or causing a public nuisance here last year. they were lorry surfing and jailed, but they have the jail sentence quashed and were freed on wednesday. one of the problems that people are saying you it is notjust against cracking, they are digesting climate change and want the government to do more about it. their concerns are they don't think cracking interfaith industry. they began cracking on monday. they say it is safe and they say it is an important part of our energy mix. they say for the next 30, 1:0, it energy mix. they say for the next 30, 40, itare energy mix. they say for the next 30, 40, it are years, energy mix. they say for the next 30,40, itare years, this energy mix. they say for the next 30, 40, it are years, this could eat home—grown energy, a stopgap of renewa bles home—grown energy, a stopgap of renewables running. people say they don't want it and they say they will carry on with it thinks into this industry is stopped. europe and japan have launched a joint mission to mercury, the planet closest to the sun. the two spacecraft will take seven

years to reach their destination. our science correspondent jonathan amos has more. the beginning of a very long journey. bepicolombo is setting out on a 9 billion kilometre trek to the inner solar system. this is europe and japan's first mission to the planet mercury, and it'll be hugely challenging. where thejoint probes are headed so close to the sun, it's as hot as a pizza oven. novel technologies must protect the spacecraft from the hellish conditions. scientists hope they'll make a raft of new discoveries. mercury is an oddball. it has an oversized iron core that no—one has yet explained, and surface materials that shouldn't be there in so hot an environment. our current theories of solar system formation, including the earth and the other planets, can't explain mercury. it's an anomaly. so we need to go to mercury and find out more information about the planet

so we can really understand how our solar system formed. british teams are heavily involved. they've built instrumentation and spacecraft components. the sun's immense gravity will pull hard on bepicolombo. this means the probes must be careful not to go too fast and overshoot mercury. an arrival date has been set for 2025. jonathan amos, bbc news. a fireworks display in southern england is to be postponed because ofa england is to be postponed because of a whale that has taken up residence in the river. the whale, nicknamed ‘benny‘, was first spotted in the river near gravesend, east of london, on 25 september. the fireworks were due to be set off from a barge in the thames, but the local council says that benny's safety must take priority. any thoughts on that, you can reach me on twitter. banks were watching. —— thanks for watching.

then it out in the skies in north yorkshire. there were some differences. western parts of scotla nd differences. western parts of scotland is on this, hill fog, patchy light rain and drizzle and here is another contrast. some persistent rain through the morning. as it moves into northern england, the rain tends to fizzle out. just left with a band of cloud and the odd spot of rain. at year showers for the far north of scotland, increasingly windy. light winds, still some sunshine across southern and south—eastern england. temperatures up to 18 or 19 celsius. one last day of autumn warmth, and

white widely 14 to 17 celsius on sunday. here is our band of cloud continuing to weaken as itjourneys south and east, clearer skies developing into a monday morning. more of a breeze, dry air. me stand fog shouldn't be too much of a problem first thing on monday morning. we noticed a dip in the temperature across northern ireland, northern england and scotland where temperatures are getting closer to freezing. an area of high pressure is building, a notice a squeeze in the isobars. strong winds coming to the isobars. strong winds coming to the north—east. further outbreaks of rain. further south across scotland into northern ireland, much will see the new week with an empty of sunshine. a caller feel. the new week with an empty of sunshine. a callerfeel. a brisk northerly wind. to compare to the highs of 19, 20 celsius, it will be more like 12, 13 celsius on monday afternoon. a similar day on tuesday.

this really dominant feature too much of next week. some windy conditions in the far north of scotland, and looks like rain could filter a little bit further south. down towards the central delta, maybe towards the borders on thursday. elsewhere, further south, a good deal of sunshine but a brisk north or north—westerly wind with temperatures just 12 to 14 celsius. to sum up the week ahead a way from the far north of scotland it is looking mainly dry, some sunshine but it is likely to turn colder by nick weekend. —— next weekend. this is bbc news. the headlines: turkey has promised to reveal every detail about the killing of the journalist jamal khashoggi, who died inside the saudi consulate in istanbul. there has been international condemnation after riyadh said mr khashoggi died as a result of a fist—fight. thousands of migrants remain stranded on the border between guatemala and mexico,

after mexican police stopped them entering the country en route to the us. one report though says dozens of women and children among the migrants, who are mostly from honduras, will now be allowed into mexico. several million afghans have voted in parliamentary elections, the first to be organised entirely by the government since 2001. polling stations which could not open on saturday plan to do so on sunday. but there has been violence. 15 people were killed by a suicide bomber in kabul.