Any probe is likely to examine 999 call grading. There is no suggestion that the pensioner had been assaulted.
The spokesman said: “CPR was performed and an ambulance was called. He was taken to hospital but sadly died later.”
A post-mortem examination to establish a cause of death is due to take place later today.
No arrests have been made.
Mr Singleton’s son, Billy was too upset to comment on the tragedy. However neighbours living on Houseley Avenue, where Mr Singleton had lived for several decades, described him as a friendly, neighbourly man and spoke of their shock at his sudden death.
Roy Edwards paid tribute to the father-of-two and said he had lived on his own since his wife died around 10 years ago.
He said: “Bill was a belting bloke. He was a really friendly neighbourly man.
“Around this time he usually starts putting lights up for Christmas. He was always out in his garden.
“He has lived here a long time. We’ve been here since 1968 and Bill and his wife were here before then.
“It’s so sad, especially if it’s over a car.
“He was a nice bloke Bill - we always had a chat.”
Another neighbour, who did not want to be named, said: “We’re not really sure what happened. Part of the road was cordoned off this morning and the police have been here since last night. They were there all night.
“There has been a police officer stood outside the house all day.
“There were forensics officers there too. They have been going in and out all day.”
Det Insp Richard Ennis confirmed the death is not being treated as suspicious.
In a statement, he said: “We are currently supporting the man’s family who are obviously upset with their loss as we continue to investigate the circumstances of what happened.
"At this moment in time, we are not treating his death as suspicious but I would ask anyone who was in the Housley Avenue area at around 8.45pm and may have witnessed anything to call police.
“As with all incidents where someone has died and there has been police contact, there has been a mandatory referral to the Independent Police Complaints Commission.”