Police have confirmed that a retired lecturer found dead at his Edinburgh flat was murdered.

Roger Gray is the third gay man to have been killed in the city in the last month but police say there is no evidence to link the deaths.

He was found stabbed to death in his hallway on Saturday morning after neighbours reported a gas leak.

Today, reports claimed that his flat in Merchiston Crescent had been locked from the inside.

Mr Gray’s neighbour Bill Coventry said he had a key to the retired lecturer’s flat in case of emergencies.

Mr Coventry, who lives in the flat above, said he tried to get into Mr Gray’s flat on Saturday after smelling gas in his bedroom.

According to the Scotsman, he said: “I couldn’t get into his flat. It was locked from the inside because it was like Fort Knox. I’m glad I didn’t get in because it was full of gas and also he was there.”

Police said the death was being treated as suspicious and a post-mortem examination has now confirmed that Mr Gray, who taught at Heriot-Watt University, was murdered.

Officers are appealing for his friends to come forward with any information to “build a fuller picture of his background”.

There is concern in Edinburgh’s gay community that three gay men have been found dead in the last month.

John Carter, 44, was found dead in a lift in a block of flats on February 27th. He died in hospital several hours later and friends speculated he may have been killed because of his sexuality.

On the same date, a man was found dead in Pilton. The Daily Record reported that the man, who cannot be named for legal reasons, was gay.

Police say the deaths are unlikely to be connected and Detective Chief Inspector Gareth Blair said: “We recognise the potential concerns that these tragic deaths may have caused within the LGBT community, and we are making contact with LGBT groups and organisations in order to provide them with reassurance and advice.

“It is important to stress at this stage that there is nothing to indicate a link between the three deaths. However, and as always, we are keeping an open mind in terms of our inquiries.”