
A “final” picture of PC Keith Palmer taken shortly before he was killed in the Westminster attack has emerged.
The photo was taken by US tourist Staci Martin as she posed with the officer 45 minutes before he was stabbed by Khalid Masood outside Parliament.
It has emerged Masood, 52, was born Adrian Elms in Dartford, Kent. It is said he used a number of aliases and was known to police.
PC Palmer, 48, was one of four victims killed on Wednesday.
Masood drove into pedestrians on Westminster Bridge before crashing his car into railings and then running into the grounds of Parliament, armed with a knife. He was shot dead by police.
Aysha Frade, a teacher in her 40s, and US tourist Kurt Cochran, 54, were killed on Wednesday, while a 75-year-old man died on Thursday evening after his life support machine was turned off.
Three women and five men have been arrested in London and Birmingham on suspicion of preparation of terrorist acts.
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- What we know so far
Ms Martin was on a visit from Florida to London when she asked to take a picture with the officer outside Parliament.
“It’s my first time in London and I see his hat and I’m like I have to take a picture of him with his hat,” she told ABC News.
“I walked up to him and said ‘do you mind if I take a picture?’ He said ‘no problem’, he was really nice.”
Less than an hour later, Ms Martin was in a taxi when she heard there had been a shooting and saw a helicopter and emergency vehicles.
She recognised PC Palmer from the photo released after it was confirmed he had been killed in the attack.
Ms Martin believes the picture with the officer must be one of the last photos of him taken alive and she feels “obligated” to get it to his family, adding: “I just want to make sure they have that of him.”

The so-called Islamic State group has said it was behind the attack.
The Metropolitan Police said there had been no prior intelligence about Masood’s intention to carry out an attack.
But he was known to the police and his previous convictions included causing grievous bodily harm, possession of offensive weapons and public order offences. He was believed to have been living in the West Midlands.

Masood is also believed to have lived at various times in Crawley, West Sussex, and Rye and Eastbourne, both in East Sussex.
He also appears to have been convicted of a knife crime in 2003 in Eastbourne.
Car hire company Enterprise said the vehicle used in the attack had been rented from its Spring Hill depot in Birmingham.
The BBC understands Masood hired the Hyundai SUV in person, giving his profession as a teacher.
The Department for Education said it had no record of him having worked as a qualified teacher in English state schools.
It appears that he styled himself as an English tutor at one point.
Immediately before the attack, Masood had stayed at a hotel in Brighton.
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The fact Masood was originally called Adrian Elms raises the possibility he changed his name after converting to Islam, said the BBC’s home affairs correspondent Danny Shaw.
“Although there’s no confirmation of that, it could help investigators understand the path he took before carrying out the attack,” he added.
The Met Police says detectives are continuing to search a number of addresses, including one in Carmarthenshire, three in Birmingham and one in east London. Addresses in Brighton and south-east London have also been searched.

PC Palmer’s family said in a statement he would be remembered as a “wonderful dad and husband”.
They also described him as “a loving son, brother and uncle. A long-time supporter of Charlton FC.

“Dedicated to his job and proud to be a police officer, brave and courageous. A friend to everyone who knew him.
“He will be deeply missed. We love him so much.”
A JustGiving page set up for the family of PC Palmer has raised more than 360,000 in less than 48 hours.
The Met said that as a mark of respect, the constable’s shoulder number, 4157U, would be retired and not reissued to any other officer.
The identity of the 75-year-old man who was confirmed as the fourth victim has not yet been released.
Tributes have been paid to the other two victims as details of their lives emerged.
Mrs Frade worked at a sixth-form college, just a few hundred metres from the bridge, while Mr Cochran was from Utah, in the US, and had been visiting the capital with his wife Melissa, who is in hospital with serious injuries.

The principal at DLD College, Rachel Borland, said she was “highly regarded and loved by our students and by her colleagues”.
According to a family statement, the Cochrans had been celebrating their 25th wedding anniversary and were due to return to the US on Thursday.
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Police have said five people remain in a critical condition in hospital and two have life-threatening injuries.
A total of about 40 people had been treated in hospital, police said.

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