Seven people have died following a terror attack in central London.
The assault began on Saturday night after 10pm when a van veered off the road and barreled into pedestrians on London Bridge.
Three men exited the van with large knives and attacked people at bars and restaurants in nearby Borough Market, police and witnesses said.
A police officer was also stabbed in the face as he rushed to help the victims.
The attack unfolded quickly, and police said officers had shot and killed the three attackers within eight minutes.
Police specialists collected evidence in the heart of London after a series of attacks described as terrorism injured 48 others.
Metropolitan Police Commissioner Cressida Dick described the incident as a "terrifying experience for many people".
Prime Minister Theresa May called an emergency security cabinet session Sunday to deal with the crisis. Most political parties suspended campaigning in respect for the victims and their loved ones.
The violence turned a summery night in an area packed with revellers into a scene of panic and chaos, with officers running through crowded streets screaming for people to flee.
Lifeboats on the River Thames helped evacuate the area.
London Bridge train station was shut down, while trains and buses were ordered to pass straight through the area. On Sunday morning, the Thames was re-opened for boats but the London Bridge area remains cordoned off and many officers were on the scene as of 10am.
Emergency officials said 48 people were treated at London hospitals and a number of others suffered less serious injuries.
The Metropolitan Police force declared the attacks "terrorist incidents," but there was no immediate claim of responsibility.
Britain was already on edge after a suicide bombing two weeks ago at an Ariana Grande concert in Manchester that killed 22 people and injured dozens of others.
Grande and other stars are scheduled to perform a benefit concert for victims Sunday night. Officials said the concert would go ahead.
The latest attacks come just days before Thursday's general election.
Ms May's Conservative Party had been expected to win by a wide margin but recent polls have showed the race tightening. Ukip said it would not suspend its campaign.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies