A KNIFEMAN had reportedly been shot outside Parliament after charging gates and attacking officers.
Witnesses also said a car mowed down a dozen pedestrians on Westminster Bridge before crashing into the gates outside Parliament.
A Reuters photographer reported at least a dozen people injured on Westminster Bridge and photographs by the news agency show people lying on the ground, some bleeding heavily
Earlier reports suggested sounds of an explosion were heard but this has not been confirmed.
The Prime Minister was seen in the voting lobby at the time of the attack, she was bundled into a car and rushed from the scene.
A witness reported: “We heard a loud bang, lots of shouting and men running around.
Someone rushed through, attacked a policeman.
“He appeared to be carrying a knife or a gun. We then heard gunfire, five or six rounds.
“The man approaching one of the police officers with a knife.”
Another witness told Sky News a man was seen walking towards a policeman with a knife in his hand, having already assaulted another policeman.
Metropolitan Police say they are treating it as a terrorist incident “until we know otherwise. The Prime Minister was “driven away” as emergency safety procedure kicked in and according to US President spokesperson Sean Spicer, Donald Trump has been briefed on the incident.
A medical helicopter has landed outside the Houses Parliament to treat victims.