A 98-year-old man who was attacked and robbed in his own home has been left fighting for his life.
Police are seeking witnesses after the victim, Peter Gouldstone, was found with a head injury and his body heavily bruised.
Officer were called to his home in Evesham Road in Enfield, north London, at around 10am on Tuesday.
They found evidence of a disturbance in the house and a number of items were missing, including a Toshiba television and personal belongings.
Paramedics tended to the pensioner, who was taken to an east London hospital where police said he remains in a life-threatening condition.
Detective Inspector Paul Ridley said: "This was a brutal and senseless attack on a vulnerable pensioner in his own home. The level of violence used was completely excessive."
He said the victim spoke to a relative on the phone on Monday at 2pm and had not raised any concerns.
"We are therefore confident, the attack has taken place in the 20-hour window between then, possible Bonfire Night, to when he was discovered," he said.
Anyone who may have seen any persons acting suspiciously in the area are being urged to come forward and contact police.
Mr Ridley said patrols have been stepped up in the area.
One neighbour, who did not wish to be named, said she rang his son on Tuesday morning after noticing Mr Gouldstone's garage door was open, which she said was "unusual".
"His son came and then police and an ambulance were here until it was dark," she said.
"I've known him for many, many years and he has a charming family. It's not nice, you just have to lock up and hope."
Pio Gomes, 78, said Mr Gouldstone was rarely seen outside his home since his wife died several years ago.
He said: "After that he wouldn't come out much. I used to take his bins out for him because he wasn't steady.
"His son Simon used to come round and take him out, take him shopping.
"Of course it affects you because it's worrying. It's callous. Who could have done this to an old man like him?"
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A police cordon was set up in the area and the fence of Mr Gouldstone's garden appeared to have been knocked down.
Anyone with information can call Enfield CID via 101 quoting CAD 2140/6Nov, or by tweeting @MetCC under Operation Name 'Burrow, or contacting Crimestoppers anonymously on 0800 555 111 or online at www.crimestoppers-uk.org