The MP for Wycombe Steve Baker has tweeted to say that he is safe after a policeman was stabbed and his attacker shot earlier today .

In a major incident which is being treated as a ‘terrorist incident’ by the Metropolitan Police, several pedestrians were hit by a grey Hyundai on Westminster Bridge before it crashed into railings.

Reports have surfaced that the driver then ran through the gates of the Palace of Westminster and stabbed the policeman.

Eyewitnesses said he was shot by police as he approached a second officer clutching his knife.

There is believed to have been a ‘suspect package’ found outside the Parliament and four people have died.

MPS have been ordered to stay in the chamber or their offices.

Mr Baker wrote: “Incident in Parliament - the Wycombe and ERG teams are safe and secure. Many thanks to those enquiring by SMS.”

A joint statement by the Speaker of the House of Commons John Bercow, MP for Buckingham, and the Lord Speaker, Lord Fowler, reads: “An extremely serious incident has occurred in the Westminster area this afternoon.

“The Metropolitan Police is dealing with this and an investigation is underway.

“On behalf of Members of both Houses of Parliament, we wish to offer our thoughts to all those affected and their families.

Reports of a shooting outside the Houses of Parliament

“We would also like to that express our gratitude to the police and all emergency services.”

Commons leader and Amersham MP David Lidington made a 20-minute statement to the House about the incident at Westminster.

During his statement, he said: "Colleagues will have appreciated that events have been moving rapidly and I want to emphasise that the knowledge that I have which is definite is so far very limited.

"What I am able to say to the House is that there has been a serious incident within the estate. It seems that a police officer has been stabbed; that the alleged assailant was shot by armed police.

"An air ambulance is attending the scene to remove the casualties. There are also reports of further violent incidents in the vicinity."

Chesham and Amersham MP, speaking from the Palace of Westminster this afternoon, said: "The police responded very quickly and their priority is to keep the people of London safe.

"They and the emergency services have acted very quickly in response to what the Metropolitan Police have confirmed to be an ongoing investigation into a terrorist incident."