A man believed to have been killed by carbon monoxide poisoning may have been lying dead in his flat for two days.

A man, said by police to be in his 60s, was found dead at a block of flats in Manor Vale, just off Boston Manor Road, Brentford, on Monday (September 7).

On Tuesday (September 8), he was named as Robert O'Donnell by a neighbour, who described him as a "lovely man" and a passionate Liverpool FC fan.

Jim Gorman, who lives across the stairwell from Mr O'Donnell's first-floor flat, said the married couple upstairs had first been taken to hospital on Sunday morning (September 6)as they were feeling unwell.

They were discharged later that day, he said, only to call for an ambulance again the following morning as they were feeling even worse.

This time, paramedics suspected the odourless but lethal gas carbon monoxide may be to blame.

Mr Gorman said the ambulance crew had alerted people in neighbouring flats but there was no answer from Mr O'Donnell's home despite a light being on.

Police were called and broke down the door to find him dead.

Police said one other person, believed by getwestlondon to be one of the upstairs neighbours, had been taken to hospital with suspected CO poisoning.

That person remained in hospital on Monday afternoon, police said, but their condition was not thought to be serious.

'Very friendly'

Mr Gorman said he understood a faulty gas heater in Mr O'Donnell's flat, possibly switched on for the first time after the summer, was to blame.

He said he thought the fumes had seeped upstairs, poisoning the couple above.

Mr Gorman said he believed Mr O'Donnell, known as Bob, had worked for the bakery firm Greggs as an electrical engineer and was planning to retire later this year or early in 2016.

He said he had lived in the block for about 25 years and originally came from Liverpool.

"He was a lovely man. He kept himself to himself but was very friendly when you spoke to him," he said.

"We would often chat and shake hands. He liked his football and was a big Liverpool fan.

"Everyone here's in shock and I think all those people like me who didn't have a CO detector have now ordered one. It's a wake-up call.

"It's very sad. I guess the only positive is that he probably would have drifted off in his sleep and wouldn't have suffered."

National Grid engineers switched off the gas supply to surrounding properties on Monday as a precaution but they are due to be reconnected later on Tuesday.

Police have said Mr O'Donnell's death is not being treated as suspicious.

They have urged people to get their gas appliances checked by a Gas Safe engineer and to fit a CO monitor.