Prime Minister Theresa May was bundled into her car by a plain-clothes police officer and driven quickly from the scene as the attack unfolded. She will chair a meeting of the Government’s emergency Cobra Committee.
Scotland Yard said the attack, which comes a year to the day after the terrorist atrocities in Brussels, was being treated “as a terrorist incident until we know otherwise”.
Witness Jayne Wilkinson said: “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.
“And then there were three shots fired, and then we crossed the road and looked over. The man was on the floor with blood.