Four people are dead after a knifeman ploughed a car into crowds outside the Houses of Parliament then stabbed a police officer in a major terror attack.

Among the four killed were the policeman, two pedestrians and the attacker, who was shot by armed officers.

Twenty people were hurt, some suffering "catastrophic" injuries, when terror struck at the heart of Westminster this afternoon.

Gunshots and panic caught on camera

Witnesses described hearing people screaming and seeing bodies scatter as the car mounted the pavement and crashed into railings just in front of the Houses of Parliament.

The attacker then ran from the car armed with two knifes and and stabbed two police officers before being shot by armed police.


Metropolitan Police Assistant Commissioner Mark Rowley confirmed one of the officers had died in the attack along with three other people, one of them the attacker.

Police update on Westminster terror attack

The man, described as Asian and in his 40s, was pictured on a stretcher after medics had attempted to save his life.

Foreign minister Tobias Ellwood had fought in vain to keep the officer alive by giving him mouth-to-mouth on the cobbled courtyard area in front of the Houses of Parliament.

Among those injured by the car on Westminster Bridge were three police officers on their way back from a commendation ceremony and three teenage students on a trip to London from France.

Image: The Westminster attacker being tended by medics

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

Among those led to safety from the building were a group of primary school children who had been on a sightseeing trip.

Bomb squad officers were called in to deal with a suspicious package found in a vehicle.

Westminster attack: Eyewitnesses recall the horror

Sightseers on the London Eye were held inside the viewing pods.

Assistant Commissioner Rowley said they believe there was only one attacker but there was a "full-scale" counter terrorist investigation under way.

He moved to reassure the public, saying that extra police officers, both armed and unarmed, would be patrolling the streets in the coming days.

Image: A map showing what happened in the Westminster terror attack

He said: "This is a day we plan for but hoped would never happen. Sadly it is now a reality.

"We will continue to do all we can to protect the people of London."

Witnesses described seeing an "Asian guy in his 40s" 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: "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."

Image: The scene on Westminster Bridge following the terror attack Image: London Ambulance Service said paramedics had treated at least 10 patients on the bridge Image: Injured people assisted by passers-by Image: A number of pedestrians were hit by a grey Hyundai i40 Image: Witnesses say they saw the car travelling at high-speed before it crashed Image: Police are treating the incident as a terrorist attack Image: The scene on Westminster Bridge as seen from Parliament Image: An armed police officer runs across the road Image: Paramedics treat an injured person Image: A member of the public is taken away in an ambulance Image: Extra police officers have been deployed in London following the attack Image: Emergency services on the River Thames Image: A paramedic at the scene of the Westminster attack /

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."

One of the key witnesses to the attack was the Acting Commissioner of the Metropolitan Police, Craig Mackey. He was unable to make a statement because he was giving vital evidence to officers.

The Government has said it will chair a meeting of the Government's emergency Cobra committee later today.

A 10 Downing Street spokesman said: "The thoughts of the PM and the Government are with those killed and injured in this appalling incident, and with their families.

"The PM is being kept updated and will shortly chair Cobra."

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.