The World Tonight

Dr Usama Hasan, a former radical Islamist who is now head of Islamic studies at the counter-extremism think tank Quilliam Foundation, tells the BBC that Khalid Masood's profile "is one we've seen before".

He added that "we mustn't be naive about the power of extremist ideologies".  

Image source, Getty Images

Foreign Office minister Tobias Ellwood was greeted by an armed police officer outside Parliament this morning.

Mr Ellwood, a former soldier, gave mouth-to-mouth resuscitation to PC Keith Palmer and attempted to stem the flow of blood after the attack in New Palace Yard. 

Mr Ellwood was pictured with blood on his face and clothes. 

His actions attracted admiration from his Westminster colleagues and police officers.

The 15th-Century Ottoman-era Old Bridge in the Bosnian city of Mostar has been lit up in the colours of the Union Jack as a show of solidarity with the people of London and more widely across the UK.

Michael Petersen, a regular at the Preston Park Hotel in Brighton where Khalid Masood stayed before he went to London to carry out the attack, says they came across each other at the reception desk.

He told the BBC Masood was polite and is shocked he was behind the attack.    

A white rose has been placed in the gates outside the Palace of Westminster to pay tribute to those affected by Wednesday's attack.

Image source, PA

Mark Rowley, Acting Deputy Commissioner of the Met, has reacted angrily after being asked about his boss's actions at Parliament, after it was revealed that the acting head of Scotland Yard, Craig Mackey, was rushed away in the aftermath of the attack. 

Detectives who are investigating are treating Mr Mackey as a significant witness as he was at the scene and he had to make a statement of what he saw. 

But when asked about why Mr Mackey had not stayed at the scene, Mr Rowley said: "It's frustrating that we get nonsense like this from armchair critics." 

He added that nine people remained in custody - including the two arrested overnight. 

Assistant Deputy Commissioner Mark Rowley has said there will be an "enhanced" armed and unarmed police presence over the next few days.

There will be almost double the number of armed officers in London, with up to a third more on duty elsewhere in the UK. 

Image source, EPA

Leslie Rhodes, the fourth victim who died in the attack, was "a lovely man", said his friend of 24 years Philip Williams.

He said "it's a crime he's been taken" and described the retired 75-year-old window cleaner as someone who "would do anything for anybody".  

One former colleague of PC Keith Palmer has told how the police officer saved her life after she was involved in a serious crash while on duty in 2007.

Nina Whitehead from south-east London was so badly hurt she had to retire.

“I literally owe him my life... I want everybody to know what a wonderful man he was," she told LBC.

“I was the passenger and he was one of the police officers who actually helped save my life.

“He didn’t just do his job to go and get paid. He actually cared about the people."

Others have also been posting their selfies taken with the officer.

Image source, Staci Martin

Image source, WILL ROBINS/TYLER CHATTERLEY-RUSSELL

This strongly worded message is among the many flowers and tributes outside the Queen Elizabeth II conference centre in Westminster. 

The note condemns Khalid Masood and says he was not a man of faith.

Image source, PA

Dominic Grieve, chairman of Parliament's intelligence and security committee, said there was no evidence at present to suggest that Khalid Masood's "activities could have been stopped before he came on to the bridge in his car".

He told Radio 4's Today programme that about 12 plots had been stopped over the past 18 months and the UK had been "extremely fortunate... it really has been a miracle it hasn't happened sooner".

Asked about arming all police officers, Mr Grieve said: "The idea that arming all police is going to be a panacea and a solution to this type of problem may well be mistaken."

Oval Tube station in south London posts a regular Thought of the Day - this time it's in tribute to those affected by the attack at Westminster.

Image source, Getty Images

Image source, Getty Images

A fund-raising appeal set up in memory of PC Palmer has raised over £430,000.

It was set up by the Metropolitan Police Federation - who represent rank and file officers.

Fellow officers and members of the public have also continued to leave flowers and messages outside Parliament, New Scotland Yard and at the National Police Memorial in Westminster.

At least 50 people were injured in the attack with 31 needing hospital treatment. Those affected include a cross-section of ages and a variety of nationalities. People hurt included 12 Britons, three French children, two Romanians, four South Koreans, two Greeks, and one each from Germany, Poland, Ireland, China, Italy and the United States.  

Dominic Casciani
Home Affairs Correspondent

Image source, AP

Khalid Masood was born in Kent and most recently lived in the West Midlands.

He is also believed to have lived at various times in Crawley, West Sussex, and Rye and Eastbourne, both in East Sussex, as well as Luton and east London.

He described his profession as a "teacher" - although the BBC has been able to confirm that he never worked as a qualified teacher in English state schools. 

He had never been convicted of a terrorism offence but the prime minister said he was "once investigated in relation to concerns about violent extremism".

We don't know at this stage what that particular investigation was and how he was connected to it.

Here are just some of the possibilities of what that could mean:

• He was an associate or friend of a main suspect who was being monitored in some form - but turned out, at the time, to not apparently have any extremist leanings
• He could have been closer to an inner circle of aspiring extremists - but he personally was not considered to be a risk and so the operation was focused on others
• There could have been more concerning intelligence about his ideology and intent - but there was nothing that could make a criminal charge - and in time he was discounted as a serious threat

He could, at the highest end, have been arrested in the past as part of an operation and later released without charge.

His last conviction came when he was 38 or 39. In general terms, that's quite late on in life for your average angry young man stuck in a world of petty criminality, violence and robbing.

Read more from Dominic about the attacker here

Assistant Deputy Commissioner Mark Rowley, Scotland Yard's top anti-terror officer, updated reporters on the progress of Scotland Yard's investigation this morning. 

He asked the public to come forward if anyone "knew Khalid Masood well" or "understands who his associates were".

Leslie Rhodes, 75, from Streatham in south London is the fourth victim to be identified.

Military veteran Mike Crofts, who witnessed the attack and rushed to help PC Keith Palmer, told BBC Breakfast this morning that it was his military training that made him react and try to help.

"Unfortunately despite our best efforts we were unable to save him. He was at the time surrounded by a whole host of colleagues who really loved him. We held his hand through the experience, talked to him throughout."

Watch his emotional interview here...

Image source, AP

Portuguese national Francisco Lopes was left with leg injuries and severe cuts to his hands when he was hit by Khalid Masood's car on Westminster Bridge.

"The adrenaline just started to take over me, I didn't want to die so I was just like 'yeah, I'm going to be okay, I'm going to try to convince myself that I'm going to be okay' and that my legs were going to be okay," he said.

The 26-year-old was on his way home from working a shift at a shop in St Thomas' Hospital - opposite Westminster - when he was struck.

He said: "I was horrified because I was scared for my life, you know, I said I didn't want to die.

"I'm happy to be alive but sleep is more difficult, difficult because I see the car hitting me, I see it all the time."

Today Programme
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