A randy Thai man died after suffering a heart attack while having sex on a building site.

Pairat Khetkaew, 61, is said to have been romping in a pile of sand with his younger girlfriend in her 30s before collapsing in Samut Prakan province, Thailand on May 1.

Shocked locals saw Pairat having sex with the woman then later found his body and called the emergency services but paramedics were unable to revive him.

Police said that he had suffered a heart attack after 'finishing sexual activity'. The woman left after he passed out and collapsed back into the pile of sand.

Police Lieutenant Colonel Sunthorn Phimphan said: ‘The deceased likely suffered from shock leading to congestive heart failure after he completed the sexual activity.

'A search of the scene found no signs of foul play but it was clear that the dead man had been having sex with someone. His body will be sent to the Institute of Forensic Medicine to find the real cause of death.’

Officers interviewed resident Lampai Ponamat, 43, who said she had just started drinking when she heard the street dogs barking unusually loudly.

Lampai quietly walked out of her home to check what was going on, but as she looked through the neighboring house, she was shocked to discover a couple making love on a pile of abandoned construction materials.

Stunned Lampai continued to watch the pair in an effort to discern their identities in the darkness. However, after a few moments, the male figure suddenly collapsed to the ground.

Lampai said: ‘Right after the man finished his business and fixed his pants, he fell hard and breathed very softly. I remember hearing the woman shouting in words I couldn’t understand.’

Lampai called her family for help and contacted local police. Officers later found the body of Pairat lying on his back close to the alley’s entrance.

Pairat was only wearing a pair of black shorts that were unzipped. Police tried to revive him to no avail.

Physical examination revealed no wounds, while semen stains were found on his crotch and the tip of his penis.

Officers also investigated and found that Pairat lives in the neighbourhood and sells sweets in a market for a living. His partner, a lady in her late 30s, was identified as a woman who lives in the same area.

Police Lieutenant Colonel Sunthorn Phimphan added: 'The dead man may have had a health condition that caused the heart attack but we will need to speak with his family and doctors to confirm this.'