A paranoid schizophrenic who died after being set on fire was killed over a drugs debt, his mother told his inquest today.

Anthony Billy's body was found alight in Croham Hurst Woods on January 19, 2011, and the burns were too severe to save him.

His death was initially treated as non-suspicious, after it was believed Mr Billy had set himself on fire.

But the police investigation was reopened last September and, giving evidence at the inquest at Croydon Coroner's Court, his mother Sandra Billy said she had spoken to her neighbour's window cleaner about what had happened.

The court heard Darren, the window cleaner, and her son would often go to a house near Portland Road, South Norwood, to smoke drugs.

Mrs Billy said: "He said he knew Anthony and he said he saw him on the Monday and that he was talking about these bad people that were after him and he had got rid of one and there was one he was still trying to get rid of.

"He said at the house Anthony would not have much, maybe just a puff so he doubted if he did owe that money.

"He did not think he would have taken his life and the other thing is that he suggests is that this man made him go and buy the petrol to burn him with.

"Darren said one thing that puzzled him was why he did he use diesel in the can not petrol; I felt that very alarming because I did not tell anyone [that the police had told me it was diesel].

"I felt afterwards that Darren knew more than he had told me."

She passed on the details of her conversation with the window cleaner to the investigating officer last year.

Mrs Billy told the court her son was looking forward to a family holiday to Jamaica which was planned for June of that year and had enjoyed a large family Christmas.

Anthony had spent time consoling his younger brother Andrew about the death of his girlfriend Keisha in April 2010.

In a written statement Andrew said: "I was at a very low point and I remember having a conversation around October 2010 and I told him I had thought about suicide and he said I was an idiot for even thinking about it.

"I can not believe that Anthony set fire to himself and someone else must have been there."

The court heard the pair used to smoke crack cocaine and cannabis and Anthony would fund his habit using his benefits money.

Consultant psychiatrist Dr Kim Sutherby said Mr Billy was a paranoid schizophrenic who would suffer from delusions of 'quite a bizarre nature involving aliens and insects'.

He had been sectioned on several occasions including after an incident at the House of Commons where he had tried to get into an area members of the public were not allowed to go.

She said Mr Billy, of Russell Hill Lodge, Purley, would not accept his drug taking was a problem and the drugs could stop his medicine from being as effective as it should have been.

But said he had no history of self harming and had never talked about wanting to kill himself.

The inquest continues.