Man, 75, who died in Westminster attack is named as Leslie Rhodes, from Clapham, London
Westminster attacker Khalid Masood, 52, was originally called Adrian Russell Elms
Masood spent two years teaching English in Saudia Arabia between 2005-2009
Four people are still being questioned by police, six have been released
Fifty people hurt in attack, two in critical condition, one has life-threatening injuries
Prince Charles visits attack victims at King's College Hospital in London
Image source, EPAThe level of police activity outside Parliament is unprecedented, the BBC's Eleanor Garnier says.
Two ambulances have left the Palace of Westminster in the last few minutes, she adds.
Some MPs have now been evacuated, but some remain in the chamber. They are not normally allowed to take photos there but they have been posting some on Twitter.
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This was David Lidington a little earlier, calling off today's business in the Commons.
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Lib Dem Councillor Paul Scriven is tweeting from inside the Houses of Parliament.
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One woman has died and a number of others have been hurt - including some with "catastrophic" injuries - in the incident on Westminster Bridge, a junior doctor at St Thomas' Hospital has said.
The London Eye tourist attraction, just across the Thames from Parliament, said it was on lockdown following the attack.
A spokesman said: "At present we are holding all of our guests within our attractions as per tried and tested security procedures."
Monmouth MP David Davies talks to the BBC News Channel from inside the Houses of Parliament.
He told BBC News: "We can't go in or out. I was in the area where the incident happened. We heard gun shots. We dropped to the floor.
"I heard the shots and I thought this can't be real. I was behind a pillar and I thought I will take a chance and run back to Portcullis House."
A planned evacuation of Parliament has been halted after an announcement was made saying there was a suspicious package in a vehicle and the bomb squad had been called.
Theresa May's official spokesman said: "The prime minister was brought back to Number 10 from Parliament. She is currently monitoring the situation."
The office of the Serjeant at Arms, who handles security in the House of Commons, said: "We are aware that there has been an incident that has taken place. At this early stage, we cannot comment further."
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Labour leader Jeremy Corbyn has tweeted the following statement on the ongoing incident in Westminster.
"Reports suggest the ongoing incident in Westminster this afternoon is extremely serious.
"Our thoughts are with the victims of this horrific attack, their families and friends.
"The police and security staff have taken swift action to ensure the safety of the public, MPs and staff, and we are grateful to them."
Daily Politics presenter Jo Coburn is locked inside Central Lobby.
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Buckingham Palace has declined to comment about its security arrangements following the incidents at Westminster, a short journey from the Houses of Parliament, but the gates have been closed.
The Observer's political editor tweets...
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Ken Macintosh, the presiding officer in Holyrood, has suspended the debate over a second referendum in parliament and First Minister Nicola Sturgeon has tweeted.
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The Apprentice star and member of the House of Lords tweets from inside the building.
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SNP MP tweets:
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