At least seven people were killed and dozens more injured after a van drove into pedestrians on London Bridge and several men then started stabbing passersby in what police said was a terrorist attack.
The incident began on London Bridge when a white transit-style van drove into a crowd of people "at about 50mph", according to witnesses.
Police said the van then drove to the nearby Borough Market where three men began attacking people. Three suspects were shot dead by armed police.
Three men have been shot dead after killing seven and injuring 48 more with a van and knife attack in London.
The killings on Saturday night were the second terrorist atrocity to hit the country in as many weeks after 22 were killed at an Ariana Grande concert in Manchester.
Attackers brought carnage to the streets of the capital, stabbing a police officer and revellers with 12-inch knives, reportedly shouting "this is for Allah".
The trio were pictured wearing what appeared to be explosive vests, with Scotland Yard later confirming they were hoaxes.
Armed police rushed to the scene and shot dead the three male attackers in the Borough Market area near the bridge, as authorities urged Londoners on Twitter to "run, hide, tell" if they were caught up in the violence.
The attacks came just five days ahead of a national parliamentary election on Thursday. The ruling Conservative Party suspended national campaigning on Sunday, a spokesman for Prime Minister Theresa May said.
"Following updates from police and security officials, I can confirm that the terrible incident in London is being treated as a potential act of terrorism," Ms May said in a statement as events unfolded.
The killings also occurred less than two weeks after a suicide bomber killed 22 people at a pop concert by U.S. singer Ariana Grande in Manchester in northern England.
The BBC showed a photograph of two possible attackers shot by police, one of whom had canisters strapped to his body. Hours after the attack the area remained sealed off and patrolled by armed police and counter-terrorism officers.
The London Ambulance Service said 48 people had been taken to five hospitals across the city and a number of others had been treated at the scene for minor injuries.
Streets around London Bridge and Borough Market, an area that is a major transport hub and is packed with bars and restaurants, was busy with people on a night out.
London Mayor Sadiq Khan spoke of a "cowardly attack on innocent Londoners and visitors to our city enjoying their Saturday night".
Police are responding to incidents in London Bridge, Borough Market and Vauxhaul which have left a number of people injured and one confirmed dead.
Armed police and emergency vehicles were dispatched to the scene at London Bridge after a van was seen plowing into pedestrians, where there were unconfirmed reports of bodies lying on the ground.
The Met Police later confirmed that they were responding to to reports of stabbings at Borough Market, where they said "shots have been fired".
Moments later, the force confirmed they were also responding to an incident in the Vauxhaul area.
We will have all the latest here.
There are reports of "multiple" casualties following a major incident on London Bridge, British Transport Police said.
Nick Brandon of the BTP's force control room said he had received reports of an incident possibly involving a knife and a vehicle.
The seriousness of the injuries is not yet known, he said.
He said trains were not stopping at London Bridge and Borough Market.
A BBC employee who was in Borough at the time of the attack describes people lying on the floor in blood.
Mauro Galuzzo tweeted: "Just come out of Borough Bistro where attack happen - saw man wielding knife and people on the floor in blood. In total shock"
Officers are now attending a third incident, in the Vauxhall area, the Metropolitan Police have confirmed. They have also confirmed that the first incident they responded to tonight was at 2208, after reports of people being hit by a vehicle.
Police are reportedly searching for three armed men after the incident in London Bridge.Read the full story here.
An eyewitness told LBC radio what he saw at London Bridge tonight.
The taxi driver said: "A van came from London Bridge itself, went between the traffic light system and rammed it towards the steps. It knocked loads of people down.
"Then three men got out with long blades, 12 inches long and went randomly along Borough High Street stabbing people at random."
Georgia Grantham, a software consultant, was leaving the theatre on Southwark Street near Borough Market around 10:30pm, has told The Independent of what she saw.
She said that her and her parents were initially held inside the theatre and then hustled out. She said she saw a man lying on the floor with his shirt off and "lots of police were near him".
"It was obviously an emergency scene" she said. "There were loads of sirens and flashing lights and a lot of confusion. Everyone was very panicked."
Breaking: Police at the southern cordon of London Bridge have confirmed that there is at least one fatality from the incident there.
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