Who was PC Keith Palmer and what has happened to the yob caught urinating on his memorial?
PC KEITH Palmer was stabbed to death by terrorist Khalid Masood in a frenzied attack outside the Houses of Parliament on March 22, 2017.
The heroic police officer was murdered as he defended the Palace of Westminster from the sick fanatic. 
Hero cop Keith Palmer was stabbed to death in the line of duty outside Parliament
Who was PC Keith Palmer?
PC Keith Palmer, 48, was a member of the Metropolitan Police's Parliamentary and Diplomatic Protection command.
He had been on the force for 15 years and joined after leaving the Army, having served as a member of the Royal Artillery.
PC Palmer was described as a loving husband and father.
Top anti-terror officer Mark Rowley said: "He was someone who left for work today expecting to return home at the end of his shift and he had every right to expect that would happen."
PC Palmer was unarmed when Masood - wielding two large knives - came charging towards him, shortly after he mowed down pedestrians in his car on Westminster Bridge.
Four other innocents also died in the attack after being hit by the knifeman's death motor.
The attacker was shot by police and later died in hospital.
Paramedics fought to save Mr Palmer's life, and that of his attacker, on the floor of the cobbled courtyard in front of Parliament.
Foreign Office minister Tobias Ellwood was among those who rushed to help.
Mr Ellwood, who lost his brother in the Bali bombing, could be seen pumping the officer's chest then standing above him.
It later emerged that Sir Craig Mackey, Deputy Commissioner of the Metropolitan Police, locked himself in a car during the attack and didn't rush to help PC Palmer.
He told the Old Bailey his “instinct” was to get out of the car, but he remained locked inside as he was unarmed, had no police radio or protective equipment, and was accompanied by two civilian police staff who had no formal officer training.
An inquest concluded that his murderer, Khalid Masood, was lawfully killed by police.
Why was PC Palmer unarmed?
PC Palmer was unarmed when his knife-wielding attacker struck.
Explaining why he didn't have a gun despite being charged with guarding Parliament, Mark Rowley, said: "Our parliamentary protection team are a combination of armed and unarmed officers doing different roles, and sadly the officer who lost his life today was unarmed.
"He was supported by armed colleagues who shot and killed the attacker.
"[The attacker] tried to enter Parliament and was stopped at the gate."
LONDON TERROR ATTACK
What has happened to the yob caught urinating on his memorial?
A man was photographed urinating on a memorial for hero PC Keith Palmer on June 14, 2020.
The man was photographed during an incident that took place in central London as statue-row protesters clashed with riot police.
The image has been shared tens of thousands of times on social media, including by MP Tobias Ellwood.
Mr Ellwood posted the photo on Twitter and said: "Absolute shame on this man.
"Of all the images to emerge over these few testing days I find this one most abhorrent."
Met Police Commander Bas Javid called the photo "disgusting and abhorrent."
He said: "I feel for PC Palmer’s family, friends and colleagues.
"We have immediately launched an investigation, and will gather all the evidence available to us and take appropriate action.”
The chairman of the Metropolitan Police Federation also condemned the incident.
Ken Marsh said: "How can a human being behave like that? I don't get it, it's beyond belief."
The Met Police said officers had arrested a man on suspicion of outraging public decency.
He is currently in custody in Essex after handing himself in at a police station.
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