Witnesses on scene said about a dozen people were injured on the Westminster Bridge. Another witness told Sky News that there was an “almighty crash” as a vehicle hit the railings outside Parliament.
A witness told Sky News: “Someone rushed through, attacked a policeman… he appeared to be carrying a knife. We heard lots of gunfire.”
Witness Jayne Wilkinson told the Telegraph: “We were taking photos of Big Ben and we saw all the people running towards us, and then there was an Asian guy in about his 40s carrying a knife about seven or eight inches long.”
Commons speaker John Bercow suspended the session as police responded to an incident.
White House press secretary Sean Spicer said on Twitter that President Trump had been briefed on the ongoing situation.
Trump himself said during a brief appearance Wednesday before reporters at the White House that he was just getting the news. He called it “big news.”
Prime Minister Theresa May is safe, a spokesperson told reporters.
The leader of the House of Commons said a man had been shot by police. David Liddington also said there were “reports of further violent incidents in the vicinity.”