Report of multiple casualties in incident on London Bridge

It's a very - it's a terrifying scene. "There was a scattering of people". "All Americans stand in solidarity with the people of the United Kingdom", she said. The drivers have not been caught. And police say that there have been stabbing incidents there and that they've sent in armed officers to address that. The police - the London Metropolitan Police - they're the most authoritative source for following these sorts of events in the city.

Police officers with riot shields on Borough High Street.

"Suddenly there was commotion and people were screaming".

"I could see six people on the floor not moving". It was utter chaos.

"Some people tried to leave the kitchens via the back door but some of us tried to keep people calm". We went towards Borough Market and everyone went inside (the bar). I heard what was significant gunfire.

"At first I thought it was fireworks but it was so rapid I recognised what it was". The response took about 10 minutes. "It was tremendous gunfire".

British police rushed to London Bridge after reports of a vehicle running down pedestrians.

"I was thinking: Which way do I run to get away?" he said, adding that the van then veered onto the other side of the bridge before hitting a girl. "He hit about two people in front of me and then three behind", she said.

Ms Robinson, from Birmingham, said her original tweet was able to reach many followers after it was retweeted by former Newsround presenter Lizo Mzimb a, who she once met after asking him for a selfie. She said he was handcuffed and had his shirt off.

Map of London Bridge location in London.

Witness Nick Archer told Sky News that he had seen a man lying on the ground who "looked in a bad way" and managed to flag down one of the police vans "whizzing past".

"My heart goes out to everyone in London tonight". Three of them were conscious. He was just down.

52-year-old Khalid Masood mowed down people injuring as many as 40 on the Westminster Bridge in a terror attack on London and stabbed a police officer to death as he tried to enter the U.K. Parliament.

Gerard Vowls, 47, told The Guardian newspaper that he saw a woman being stabbed by three men at the south end of London Bridge.

Pictures show medical staff attending to apparent victims of the attack and a helicopter buzzing just metres over London Bridge, one of the major arteries in the City business district.

She will hold an emergency ministerial meeting later on Sunday and Facebook has activated its safety check function for people in London to let their loved ones know they are safe.

BBC reporter Holly Jones, who was there at the time of the incident, told the broadcaster the van was "probably travelling at about 50 miles an hour" before it ran into people. So the police are checking the Thames. We drove a bit further and noticed there was another person on the right hand side of the bridge who was also not on the pavement but in the road itself. He said he threw chairs, glasses and bottles at the attackers in a bid to stop them.

Witnesses reported a vehicle hitting pedestrians and injured people on the ground. There would have been a lot of people on London Bridge. "I feel sick", one witness wrote.

Quite worrying scenes at London Bridge from above.

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