Tributes have been pouring in for Irish singer Sinéad O’Connor who has died at the age of 56 just 18 months after the tragic death of her son.

This came amid a long-running battle with mental health and substance abuse throughout her long career which started in the 1980 and 1990s.

Writer Bonnie Greer and Irish MMA superstar Conor McGregor are among those leading tributes to the singer with the latter stating she had the "voice of an angel".

READ MORE: Heart wrenching tributes pour in for singer

The late singer has been seen in Oxfordshire in the past.

Sinead O'Connor had been spotted drinking at The George Hotel in Wallingford and George Michael, who had a home in Goring, was also coincidentally seen browsing antiques shops in the town at the time.

National reports including The Telegraph have been recalling the time the singer drank in the Oxfordshire watering hole.

However, a member of staff at The George Hotel had no recollection of the celebrity visit when contacted by the Oxford Mail this morning. 

The Met Police has issued a statement regarding Irish singer Sinéad O'Connor and confirmed her death is not being treated as suspicious.

The force said: "Police were called at 11.18am on Wednesday, 26 July to reports of an unresponsive woman at a residential address in the SE24 area.

"Officers attended. A 56-year-old woman was pronounced dead at the scene.

"Next of kin have been notified. The death is not being treated as suspicious. A file will be prepared for the coroner."