The body of the missing children's television presenter Mark Speight was found hanging in a building adjacent to Paddington railway station, police confirmed tonight.
Officers are investigating how Speight managed to access the partially-disused office block and apparently take his life.
Investigators are studying CCTV footage recorded at the busy London railway terminal last Monday when Speight was last seen alive.
Concern had been growing for the safety of Mr Speight, 42, who hosted the BBC art show SMart, as he was said to have been in a vulnerable state following the death of his fiancee Natasha Collins at the flat they shared in St John's Wood, north-west London, in January.
He was initially arrested on suspicion of murdering his fellow presenter Ms Collins, 31, and supplying her with class-A drugs. Police later "cancelled" his arrest and said he was not a suspect, but friends said he never managed to recover from finding his lover dead in a bath of scalding hot water from a drug overdose and severe burns.
Mr Speight was found in Paddington railway station yesterday morning. British Transport Police (BTP) said railway workers found the body on the roof of MacMillan House at about 10am yesterday.
According to company records the office block is used as a base by several railway and bus transport firms.
A BTP spokeswoman said the body was in "a remote area out of public view" of the building, which is close to platform one of the station.
A post-mortem to find exactly how Speight died and identify how long his body lay undiscovered will take place later today or tomorrow.
Friends and relatives had made several appeals during the past week with his father, Oliver, urging him not to "give up". Responding to the news of his death, Oliver Speight said he had lost a "wonderful" son.
He said: "He will be very sadly missed. We need to come to terms with our grief at the loss of both Mark and Natasha and would ask that you would respectfully afford us the privacy to grieve privately during this tragic time."
He thanked his son's friends and colleagues at the BBC for their support throughout his career and during his recent troubles.
Lisa Ratcliff, a close friend, said she was "deeply affected" by the tragedy: "Mark was a wonderful man, a gifted artist with a warm and gentle personality, who touched the lives of so many people with his unique skills and talents."
Mark French, the agent who represented Ms Collins, said it was "dreadful", adding that Ms Collins' death and the aftermath had "just got on top of him".
"I spoke to him a few times and he just wanted to lock himself away. We were all there for him, but obviously it just got too much for the man," he said.
Jan Kennedy, of Billy Marsh Associates, Mr Speight's agent, said the firm was "absolutely devastated at the tragic news of the loss of Mark".
"Caring and compassionate in everything he did, Mark was truly gifted in life and we are proud to have represented him as a friend and client for almost 20 years," she said.
Last week, the Westminster coroner, Paul Knapman, recorded a verdict of misadventure at an inquest into Ms Collins' death.
The inquest was told the couple had consumed wine, vodka, cocaine and sleeping pills the night before her body was found in the house they shared in St John's Wood. Mr Speight had gone to bed at 4am on 3 January and awoke nine hours later to find Ms Collins' body in the bath with the hot tap still running. She had suffered 60 per cent burns to her body.
On Monday last week, Mr Speight was reported missing after failing to keep an appointment to meet his late fiancée's mother for coffee in Covent Garden at 3.30pm.
A spokeswoman for Ms Collins' mother, Carmen, said she was "devastated" and asked to be allowed to grieve in peace.