
A car is seen crashed into a fence outside the Parliament building in London on Wednesday, March 22. Police have launched a "full counter-terrorism investigation" after an attacker rammed a car into crowds of people and stabbed a police officer on Parliament grounds.

An armed police officer stands over the attacker, identified as Khalid Masood, outside Parliament. "It appeared that a car was coming towards the House of Commons mowing down pedestrians on the way," Member of Parliament Gerald Howarth told CNN. "The driver then got access to the parliamentary estate, stabbed a police officer and was shot."

Masood is treated by emergency services as police look on at the scene outside the Houses of Parliament. The Metropolitan Police say he was born in Kent, but is believed to have been living in the West Midlands recently. Police say Masood was also known by a number of aliases. "Masood was not the subject of any current investigations and there was no prior intelligence about his intent to mount a terrorist attack," Met Police said in a statement.

Member of Parliament Tobias Ellwood, in the glasses, tends to one of the injured people amid the chaos. The man the politician was trying to save was a police officer who died, a witness on the scene told CNN. Authorities identified the deceased officer as Keith Palmer, 48.

Emergency workers attend to injured people at the scene.

Medics treat a victim on Westminster Bridge.

People leave the Parliament building after the incident. Lawmakers were forced to remain in the main debating chamber of the House of Commons as police responded to the incident outside.

A person is treated at the scene.

Medical aid is provided outside Parliament.

Tourists were trapped for a time in cars on the London Eye Ferris wheel, which was stopped in the immediate aftermath of the attack.

A police officer stands guard near Westminster Bridge and the Houses of Parliament.

A person receives medical treatment at the scene.

At right, the car of British Prime Minister Theresa May is driven away from Parliament.

An air ambulance arrives at the scene.

Armed police enter the Houses of Parliament.