The Met describes the attack on Thomas O’Halloran in west London as an act of unprovoked violence.
An elderly man who was stabbed to death while riding a mobility scooter in west London has been named by police.
Thomas O’Halloran, 87, died on Cayton Road, Greenford, after being attacked just after 16:00 BST on Tuesday.
He was treated by paramedics but died at the scene, the Metropolitan Police said.
Ch Supt Sean Wilson said Mr O’Halloran had his life taken away from him in an act of “unprovoked violence”. No arrests have yet been made.
“We believe that Mr O’Halloran was stabbed on Western Avenue before managing to travel 75 yards or so on his mobility scooter to Runnymede Gardens where he flagged down a member of the public for help,” he said.
“So, please. If you saw anything we do need to hear from you.”
It is the sixth murder investigation to be launched in London in the last four days.
Mr Wilson said Mr O’Halloran was a “much-loved” member of the Greenford community and lived locally.
Extra officers will be deployed to patrol the area in the coming days to provide reassurance, he added.
“They are there to protect you and to help you,” Mr Wilson added.
“If you have any concerns or information that you want to share please approach those officers. I realised that dreadful impact that incidents like this have on our communities.
“I would like to reassure you all that we are doing all we can to solve the horrendous crimes that we have seen across London.
“Over the last few days. I stress. that London remains one of the safest cities in the world.”
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