Six people have been killed in a terrorist incident in central London in which three attackers were shot dead by police, Scotland Yard has said.
Police and ambulances were alerted at 22:08 BST to reports a van had hit people on London Bridge.
Armed officers later went to the nearby Borough Market in response to reports of stabbings in the area which is known for its restaurants and bars.
London Ambulance Service said at least 30 people have been taken to hospital.
A number of people were treated at the scene for less serious injuries.
The British Transport Police said one of its officers was seriously injured after being stabbed as he responded to the incident but he was not in a life-threatening condition.
The Metropolitan Police tweeted: "At 0025hrs 4/6/17 the incidents at #LondonBridge & #BoroughMarket were declared as terrorist incidents."
Prime Minister Theresa May described the incidents as "dreadful events" and will chair a meeting of the government`s Cobra emergency committee later.
Home Secretary Amber Rudd said the attacks were "horrific" and "targeted at people enjoying their evening with friends and family".
London Mayor Sadiq Khan said: "We don`t yet know the full details, but this was a deliberate and cowardly attack on innocent Londoners and visitors to our city enjoying their Saturday night. I condemn it in the strongest possible terms."
Eyewitnesses told BBC home affairs correspondent Tom Symonds they saw people getting out of the van after the attack on the bridge and running towards Borough Market.
Gunshots were later heard in the area while one social media user has posted a photograph appearing to show one of the attackers lying on the ground outside a pub in the food market, with what seemed to be canisters strapped to his body.
Met Police Assistant Commissioner Mark Rowley said: "The suspects had been confronted and shot by the police within eight minutes of the first call.
"The suspects were wearing what looked like explosive vests but these were later established to be hoaxes."
He said that the force`s knowledge of the incident is still growing but it is currently believed there were three attackers involved.
The attack comes almost two weeks after 22 people died in a suicide bombing at a concert in Manchester. In March, five people died in London when a car was driven at pedestrians on Westminster Bridge and a police officer was stabbed outside Parliament.
Source: BBC