An Irish pensioner found burnt to death at his home died from spontaneous human combustion, an inquest has concluded.

The West Galway coroner, Kieran McLoughlin, said there was no other adequate explanation for the death of 76-year-old Michael Faherty, also known as Micheal O Fatharta. He said it was the first time in his 25 years as a coroner that he had returned such a verdict.

An Irish police crime scene investigator and a senior fire officer told the inquest in Galway that they could not explain how Faherty burned to death. Both said they had not come across such a set of circumstances before.

The assistant chief fire officer, Gerry O'Malley, said fire officers were satisfied that an open fire in Faherty's fireplace had not been the cause of the blaze.

No trace of an accelerant was found at the scene, and there was no sign that anyone else had entered or left the house in Ballybane, Galway city.

The inquest heard that asmoke alarm in the home of Faherty's neighbour Tom Mannion had gone off at about 3am on 22 December last year. Mannion said he went outside and saw heavy smoke coming from Faherty's house. He banged on the front door but got no response, and then banged on the door of another neighbour. Gardai and the fire brigade arrived quickly at the scene.

Garda Gerard O'Callaghan said he went to the house after the fire had been extinguished and found Faherty lying on his back in a sitting room, with his head closest to the fireplace. The rest of the house had sustained only smoke damage.

O'Callaghan told the coroner that the only damage was to Faherty's remains, the floor underneath him and the ceiling above. .

The inquest heard that fire officers had been unable to determine the cause or the origin of the fire.

The state pathologist, Prof Grace Callagy, noted in her post-mortem findings that Faherty had Type 2 diabetes and hypertension, but concluded he had not died from heart failure.

His body had been extensively burned and, because of the extensive damage to the organs, it was not possible to determine the cause of death.

McLoughlin said: "This fire was thoroughly investigated and I'm left with the conclusion that this fits into the category of spontaneous human combustion, for which there is no adequate explanation."