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A son who believed he had cremated his father five years ago was surprised to switch on his television and see a familiar, if older and greyer, face staring back at him.
John Renehan's father, John Delaney, went missing from his home in Oldham, England, in 2000.
Three years later, a badly decomposed corpse, adorned with clothes similar to those Mr Delaney was wearing when he vanished, was found in bushes at Manchester Royal Infirmary.
Police failed to carry out DNA tests on the remains, but a coroner formally identified the body as that of Mr Delaney.
His son organised his cremation soon after.
Then, in April this year, Mr Renehan, an engineer, spotted his father in a BBC programme about missing people.
It showed Mr Delaney living in a care home for the elderly, having completely lost his memory.
Referring to the moment he saw his father on television, Mr Renehan said: "I knew straight away that it was my dad. I think they thought I was some nutcase."
The 71-year-old had been found wandering in a confused state around Ancoats, central Manchester, two weeks after he disappeared.
His family had filed a missing person's report, and police issued an appeal and circulated photographs, but Mr Delaney's loss of memory proved problematic.
When he turned up at Royal Oldham Hospital with severe bruising and amnesia, no one made a connection.
Unable to give any clue to his identity, he was renamed David Harrison and placed in a home.
Police believe Mr Delaney suffered a serious blow to the head 10 days before he was found.
Social workers who looked after him were unable to issue an appeal for information about him until a legal change earlier this year meant they did not have to seek consent.
Mr Renehan, 42, was reunited with his father a fortnight ago once DNA tests proved their relationship.
He now spends part of every day with Mr Delaney, whose memory is improving.
Mr Renehan said: "I have been bringing pictures in, trying to bring his memory back, and things are starting to click. But the thing that keeps popping into my mind is this other person I cremated. There is another family who are never going to know."
The Greater Manchester force has admitted its errors and apologised to the family but Mr Renehan said: "I'm not happy about the whole scenario. Somebody has got to take responsibility for their actions."
- INDEPENDENT