Westminster attack: Car ramming, stabbing and gunshots in Westminster

Two people have died and a number of others are hurt, including some with "catastrophic" injuries.

Westminster is on lockdown after a terror attack where a knifeman ploughed a car into pedestrians before stabbing a policeman outside the Houses of Parliament.

Two people have died and a number of people have suffered "catastrophic" injuries after in the incident where a number of people were mowed down on Westminster Bridge by the attacker.

Witnesses described hearing people screaming and seeing bodies scatter as the car is understood to have mounted the pavement just in front of the Houses of Parliament.

Another witness said they had seen a person in the River Thames.

The car then smashed into railings surrounding the Palace of Westminster, close to Big Ben in Parliament Square, where the attacker got out and stabbed a policeman.

As he approached a second officer, he was shot by armed police. A video has emerged showing two officers pulling up outside the Houses of Parliament and then the sounds of three shots rings out.

Parliament was immediately shut down and the Prime Minister bundled into a car as officers searched the building, evacuating floors one by one.

Staff in other buildings around Westminster were being asked by police to stay into their officers and Parliament was suspended for the day. Sightseers on the London Eye were being held inside the viewing pods.

Scotland Yard said the attack was being treated "as a terrorist incident until we know otherwise".

An air ambulance landed in Parliament Square and medics were treating a number of people who had been injured in the incident.

Pictures showed a number of people lying in the road on the bridge, another image showed a man lying bleeding at the foot of stairs next to the Parliament building.

Witnesses described seeing an Asian guy in his 40 carrying a knife and running across the bridge and towards the Houses of Parliament.

Alan Parry, of Sky Sports News, was at Westminster for a meeting when he heard "an almighty crash" just outside the underground station .

He said he could see a vehicle on the other side of the road which had crashed into some railings.

He said: "There was smoke coming this vehicle. I walked on a few paces further and saw what I assumed to be either a pedestrian or a cyclist who had clearly been hit and wasn't moving, although he did then gently move.

"The guy who I assumed was the driver of this 4x4 got out of the car and suddenly sprinted away from the scene - that was followed by four of what sounded much like gunshots.

"All of a sudden all hell was let loose. Police descended everywhere and the whole area was locked down."

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.

"He had a lightweight jacket on, dark trousers and a shirt.

"He was running through those gates, towards Parliament, and the police were chasing him."

Commons leader David Lidington confirmed a "police officer has been stabbed" and the "alleged assailant was shot by armed police" amid "further violent incidents" in the area.

He told MPs in the House of Commons: "An air ambulance is currently attending the scene to remove the casualties.

"There are also reports of further violent incidents in the vicinity of the Palace of Westminster but I hope colleagues on all sides will appreciate that it'd be wrong of me to go into further details until we have confirmation from the police and from the House security authorities about what is going on."

Buckingham Palace declined to comment about its security arrangements but it was clear some precautions had been taken as the gates, patrolled by armed police, had been closed.

MSPs have delayed a vote on a possible second independence referendum in light of the attack.

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