An investigation, led by the Surrey and Sussex Police Major Crime Team, is under way and inquiries remain ongoing, police said.
Senior Investigating Officer DCI Kimball Edey said specialist officers “are working around the clock to gather as much information as possible,” and that the force’s “thoughts are with the family and friends of the victims at this unbelievably difficult time”.
Roman Lavrynovych appeared at Westminster Magistrates’ Court on Friday and was remanded in custody.
Officers from the Metropolitan Police’s Counter Terrorism Command led the investigation because of the connections to the prime minister.
Emergency services were called to a fire in the early hours of Monday at a house in Kentish Town, north London, where Sir Keir lived with his family before the election.
Crystal Palace are celebrating a historic win in the FA Cup after a 1-0 victory against Manchester City at Wembley.
It’s the south London club’s first major trophy – and third time lucky after losing two previous finals they have played in. The win also means Palace have qualified for next season’s Europa League.
Eberechi Eze put his side 1-0 up with the game’s only goal in the 16th minute.
Man City were given a chance to equalise when they were awarded a penalty in the 33rd minute, but Palace goalkeeper Dean Henderson – who had earlier escaped a red card for a handball outside the box – saved Omar Marmoush’s spot kick.
Image: Crystal Palace’s Eberechi Eze scores. Pic: PA
Image: Man City’s Omar Marmoush after his penalty was saved. Pic: PA
It briefly seemed the south London team had gone 2-0 up after a 58th-minute strike from Daniel Munoz but the goal was quickly ruled offside.
They then held onto their 1-0 lead until the final whistle, which came after an agonising 10 minutes of injury time.
Image: Dean Henderson dodged a red card and saved a penalty. Pic: PA
Oliver Glasner’s team were the underdogs despite Manchester City having had a difficult season in the Premier League.
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Pep Guardiola’s side also lost to their neighbours and rivals Manchester United in last year’s cup final.
‘It’s all about spirit’
Palace goalscorer Eze said he had “no words” as he celebrated with his team mates.
Image: Eze celebrates after the final whistle. Pic: PA
“I can only thank God,” he told ITV. “This is special, this is what dreams are made of, for this club as well. Who would have thought we could do it?
“We’ve made history today. The tactics were good but it’s all about spirit. That’s energy, that’s everyone fighting together and doing what we had to do today.”
This breaking news story is being updated and more details will be published shortly.