1 person was killed and about 20 people were injured after a van reportedly ploughed into pedestrians on London Bridge, amid unconfirmed reports of gunfire and stabbing, British media reported.
The vehicle is reported to have mounted the pavement at the scene Saturday evening, Mirror reported in its website.
"We are dealing with an incident on London Bridge, when we have more information we will update this twitter feed," the Metropolitan police said in its Twitter account.
Transport for London said the the police have closed London Bridge and the area around it due to a major police incident, Xinhua reported.
"London Bridge: The station is closed and trains are non stopping at the request of the police," it said.
According to an eye witness: "There was a white van driver speeding into several people. It carried on across the pavement around the traffic and towards the Shard area."
Some netizens witnessed the incident tweeted that they saw people got injured and the police has come to deal with it.
One witness wrote on Twitter: "Passerby says 15-20 people have been run over. Another says 7 or 8."
"Horrific scene at London Bridge... bodies strewn over the pavement. B&Q van mounted the pavement. I feel sick," Ben Leo said in Twitter.
Armed police are said to be at the scene while people have been seen fleeing the central London landmark. London Ambulance Service said multiple resources were attending the area.
(with added information)