Attack on Westminster. Image: Met Police

Prime Minister Theresa May has told the House of Commons that the man responsible for Britain’s worst terrorist attack since 7/7 in 2005 was British born and known to the Security Service, MI5.

He’s been named as 52 year old Khalid Masood, originally from Kent but living in the Midlands.

What we know so far about suspected Westminster attacker Khalid Masood pic.twitter.com/nP6WgQvWEX

— Press Association (@PA) March 23, 2017

A minute’s silence has been held in Britain at 9.33 a.m. this morning in memory of those who lost their lives and the injured casualties of the terrorist attack in Westminster yesterday afternoon.

9.33 represents the police number for PC Keith Palmer who was stabbed to death when preventing the attacker storming the House of Commons.

Two people died when the attacker drove at speed on the pavement of Westminster Bridge catapulting a woman into the River Thames.

She was rescued by the London Fire Brigade and is in a serious condition.

The attacker was shot dead by armed police officers.

Police across #London honour those who lost their lives in the #WestminsterAttack with a one minute silence #WeStandTogether pic.twitter.com/nS6BKATrtG

— Metropolitan Police (@metpoliceuk) March 23, 2017

He received first aid from emergency first responders.

Conservative MP James Cleverly was a close personal friend of the murdered police officer.

He had served with him in the Royal Artillery many years before.

Tory MP James Cleverly pays an emotional tribute to Pc Keith Palmer who was killed in yesterday’s terror attack in Westminster pic.twitter.com/IDjN7sUJjG

— Joe Pickover (@JPickover) March 23, 2017

Another MP Lindsay Hoyle said PC Palmer ‘died defending democracy.’

“We’ve lost one of our village bobbies”

MP Lindsay Hoyle pays tribute to PC Keith Palmer, who “died defending democracy”

Theresa May: Our values will prevail, terrorists will be defeated. More: https://t.co/hO1zNr2xgD pic.twitter.com/UHfxkbjvj1

— Reuters UK (@ReutersUK) March 23, 2017

#Westminster pic.twitter.com/vLYUHSdOsY

— BBC Radio 5 live (@bbc5live) March 23, 2017

40 people have been injured in the attack.

They are from twelve different countries.

Video: A former neighbour of attack victim Aysha Frade speaks of her shock and sadness. pic.twitter.com/gFkYiDPm9d

— Catherine Wylie (@wyliecatherine) March 23, 2017

Kurt Cochran from Utah killed in terror attack in Westminster, wife Melissa seriously injured, family spokesman says https://t.co/QDecpmVKO0

— BBC Breaking News (@BBCBreaking) March 23, 2017

Her Majesty The Queen has sent a message to the Acting Commissioner of the @metpoliceuk following yesterday’s events https://t.co/jiNeA3xqFh

— The Royal Family (@RoyalFamily) March 23, 2017

#WeStandTogether with communities. Today faith leaders meet at Scotland Yard. We won’t allow terrorists to create discord, distrust & fear pic.twitter.com/PyKQ0XixFo

— Metropolitan Police (@metpoliceuk) March 23, 2017

Charlton have placed a club scarf over PC Keith Palmer’s season ticket seat in tribute 👏 pic.twitter.com/fHKXBadYT3

— PA Dugout (@PAdugout) March 23, 2017

Four killed in attack on symbol of British democracy https://t.co/6kOIizUUrm pic.twitter.com/9ptBXZn00i

— AFP news agency (@AFP) March 22, 2017

Join us in Trafalgar Square at 6pm. We stand together against this attack on our democracy and our city. https://t.co/jCMhgyOB4O

— Mayor of London (@MayorofLondon) March 23, 2017

Seven arrests have been made in raids in London, Birmingham and elsewhere following the #Westminster terror attackhttps://t.co/wViGXn08x9

— BBC News (UK) (@BBCNews) March 23, 2017