The coroner acknowledged he couldn’t provide a reason for the incident.

The death of an elderly Irish man was determined to be due to ‘spontaneous combustion’ — though investigators were left baffled by how it happened.

Michael Faherty, 76, was discovered burned to death in his home in Galway, Ireland, on December 22, 2010.

The inquest revealed that around 3 a.m., a neighbor heard Faherty’s fire alarm and noticed smoke pouring from his house. He reportedly knocked on Faherty’s front door but received no response. Another neighbor joined him, and soon the police and fire department arrived at the scene.

Upon investigation, no accelerants were detected, and there were no signs of foul play. Assistant Chief Fire Officer Gerry O’Malley determined that the fire in the fireplace was not the origin of the flames, according to Galway Beo at the time.

Additionally, there were no reports of anyone entering or leaving the home prior to Faherty’s body being discovered, The Guardian reported.

Faherty’s organs were so severely damaged by the fire that the exact cause of death couldn’t be confirmed, but it was determined he hadn’t died of heart failure, according to coroner Dr. Ciaran McLoughlin.

In the inquest, Dr. McLoughlin stated that he concluded this case fell under ‘spontaneous human combustion,’ for which there is ‘no sufficient explanation,’ noting it was his first time reaching such a verdict in his 25-year career, as reported by The Guardian.