A 64-year-old man identified as San Gray has died during marathon s*x with a prostitute after he suffered a heart attack while having s*x.

The man was found with an-hour erect p*nis despite being dead after it was confirmed he took aphrodisiac pills.

He was found lying dead by a motel cleaner who checked his room at midnight. The aphrodisiac drug identified as "the muscle" was found near his bedside.

It was gathered that the man booked into the motel last Thursday night at 7pm before ordering food to eat in the room.

According to CCTV clips, a woman was seen on camera arriving in his room at 10pm before leaving a "short time later" while the man was sprawled n*ked on the bed in Bueng Kan, northern Thailand.

Police said the man might have suffered a heart attack during the romp with the teenage girl due to the strong effect of the drug or might have had too much to eat before the hot s*x.

Police Captain Narong Srimart said: "The official opening of the door into the room (SIC). The deceased was found lying naked. But his penis was still hard and erect. We believe he had been dead for at least an hour.

"He took the aphrodisiac before having sex and had a heart attack during sex. The lady knocked on the door at 10pm but after not long left the room very quickly."