A Doncaster man may have died nine months before his body was found in his home in the town, it is feared.
The man, named locally as John Ainley, was found in his rented terraced home in Cunningham Road, Hyde Park, on Friday, according to an estate agent worker who raised the alarm.
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He said he dialled 999 after looking through the letterbox and noticing a mass of dead flies inside when he was unable to gain access to the property.
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There was also a pile of unopened letters, including Christmas cards, behind the front door.
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Andrew Melbourne, who works for Robson estate agents in Doncaster, said police officers attempting to date the time that Mr Ainley died found old style pound coins in his wallet, which were withdrawn from circulation in October.
It is understood that the dead man was in his 80s and had lived in the house for around four years.
The OAP been described as 'always friendly' and 'smartly dressed'.
Mr Melbourne it was sad that his body remained undiscovered for so long.
"We had been trying to update the gas certificate for the property for a while which is why I called at the house, looked through the letter box and saw all the dead flies, so I dialled 999 straight away," he said.
"The police officers at the scene said the Christmas cards behind the front door and the old style pound coins still in his wallet suggest that he could have been there from around October, which is when the coins went out of circulation, or earlier.
"He was a really nice gentleman, always friendly and always smartly dressed when he left home. It is sad and disappointing that nobody missed him. A couple of neighbours said they hadn't seen him for some time. One thought it was three weeks, another thought it was three months but they could not be sure.
"In years gone past a milkman would have realised something was wrong and would have raised the alarm but there is not that sense of community anymore these days."
Mr Melbourne said it was 'frustrating' that two police officers called to the house after the discovery of the body had to stand guard for a number of hours until a paramedic arrived to officially pronounce Mr Ainley died.
"Once scenes of crime officers ruled out anything untoward about the death it was frustrating to see two police officers guarding the house for hours while they waited for a paramedic to arrive to officially pronounce him dead," he said.
"There is a protocol that has to be followed but because paramedics will have had emergencies to deal with that day, the officers could have been stood there all day waiting for the death to be declared. I left at 4pm and the officers might still have been there at midnight depending on how stretched paramedics were that day. I don't know what time they left.
"I feel it was a waste of resources and the police officers' time could have been better spent fighting crime and catching criminals than standing outside a house. I hope those in charge look at this and the system in this scenario so that as many officers as possible are available to police Doncaster."
A statement has not yet been issued by South Yorkshire Police.