A grieving mother today spoke of her despair after hospital staff refused to readmit her drug addict son who was found dead five hours later.

Alan Grimshaw, 23, shouted: "I'll be back in an hour dead" when he was told police would be called if he did not leave Bradford Royal Infirmary's Medical Admissions Unit.

Mr Grimshaw, a heroin user since he was 14, was found slumped in the grounds of Hilltop Church of England School, Low Moor, later that day.

He was dead on arrival at Bradford Royal Infirmary.

An inquest yesterday heard that he had taken five times the fatal dose of heroin.

His death on January 11 this year was due to cerebral and respiratory depression from the toxic effects of the drug.

There was a syringe near his body and three fresh needle marks on his arm.

Assistant Deputy Coroner of West Yorkshire, Paul Marks, recorded a verdict of accidental death.

He said he was satisfied there had been a full psychological assessment on Mr Grimshaw. There were no definite features to show he had a high level of depression and was a suicide risk.

But Mr Grimshaw's mother, Doreen Ellis, of Whycote End, Wyke, Bradford, said after the hearing that she believed the hospital had let her son down.

She said: "I think his death could have been avoided if he had had the right help at the right time. I don't think the hospital staff did enough."

A family friend added: "What does it take to show someone might commit suicide? Do you have to go to hospital screaming and running round with a knife?"

Karen Johnson, matron on the medical admissions unit, told the inquest that Mr Grimshaw was admitted with a drug overdose on January 10.

He was discharged at 2.10pm the next day but asked to be readmitted shortly afterwards.

He said he might do it again' but Mrs Johnson said she took this to mean take heroin, not overdose on it.

He had made a full medical recovery and she thought he was being manipulative. He said he could not go home because the police were after him.

"He was told that if he refused to leave, the police would have to be called anyway. He ran off shouting: I'll be back in an hour dead'," said Mrs Johnson.

She said she believed Mr Grimshaw's overdose was "recreational" and he was saying it for effect.

Also giving evidence, Sue Morris, a mental health nurse, said Mr Grimshaw had social difficulties not mental health problems.

He had been living at the family home but left to stay with a girlfriend. That relationship had broken down and he feared he was in breach of his bail conditions.

He said he took heroin for the buzz'.

"There was no evidence of a depressive illness and he spoke positively about the future," she said.

Dr Catherine Bradley, of Sunnybank Medical Centre, Wyke, said Mr Grimshaw and his mother called at the surgery at about 4pm that day. He had overdosed on heroin in 2001 and 2004 and told the GP he wanted to kill himself.

Dr Bradley rang Sue Morris who said Mr Grimshaw could return to the hospital straight away for reassessment.

After his probation officer called on his mother's mobile phone, Mr Grimshaw became agitated and left the surgery. The inquest heard that Mr Grimshaw had been arrested 25 times in the past two years, mainly for minor thefts and assaults.

After the verdict, a spokesman for Bradford Teaching Hospitals NHS Foundation Trust said: "The hospital offers every sympathy to Mrs Ellis and Alan's family.

"The verdict of the inquest is that Alan's death is found to be accidental. This is clearly a tragedy for the family."

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