Here is a timeline of the night, in which three assailants went on a stabbing rampage after smashing into pedestrians with a van.
Here is a timeline of the night, in which three assailants went on a stabbing rampage after smashing into pedestrians with a van, killing a total of seven people before being shot dead by police:
10:07 pm (2107 GMT): The London Ambulance Service receives a first call to an emergency incident on London Bridge, a crossing between the City of London financial hub to the north and the trendy Borough area to the south.
10:08 pm: Police are called to reports of a van hitting pedestrians on London Bridge. A BBC reporter at the scene said she saw a van travelling at around 50 miles per hour (80 km/h) and casualties on the street.
Witnesses say they rushed to help five or six people who were hit by the van, including a woman who was thrown into the air by the force of the impact.
The van comes to a stop outside The Barrowboy & Banker pub on Borough High Street and witnesses see three assailants armed with knives rush out, headed for the packed bars and restaurants in the area.
10:10 pm: Police officers arrive at the scene, according to London Mayor Sadiq Khan.
10:14 pm: Paramedics arrive at the scene.
10:16 pm: Armed officers kill the three attackers outside the Wheatsheaf, a trendy pub dating back to the 19th century on the edge of Borough Market.
Italian photographer Gabriele Sciotto takes a picture of the scene showing the three assailants on the ground.
One of them appears to be wearing military trousers.
The three were also wearing belts with canisters attached to them that looked like suicide vests but were in fact "hoaxes", the police said.
11:30 pm: British Transport Police report "multiple casualties".
11:46 pm: Police release an urgent message urging people to run to a place of safety, turn their phones to silent and call the police only if safe to do so.
It is the first time police have released this particular message, which was designed in the wake of Paris terror attacks in November 2015.
00:25 am: London's Metropolitan Police Service declares the events at London Bridge and Borough Market as "terrorist incidents".
00:38 am: Prime Minister Theresa May condemns "a terrible incident" and says: "Our thoughts are with those who are caught up in these dreadful events".
04:00 am: National counter-terrorism policing chief Mark Rowley says six people have died and three assailants have been shot dead by police.
He says one of the injured is a member of the British Transport Police who was stabbed in the face.
Around 08:00 am: An emergency ministerial meeting hosted by May begins after the Conservatives and main opposition Labour parties suspend campaigning ahead of a general election on Thursday.