An American tourist was found dead in a pool of blood surrounded by shards of glass at a resort in southern Thailand.

Thomas Kristian Russell, 45, from Illinois, checked into the Akanake Resort for a mental health retreat but reportedly violated rules when he slipped out to drink alone in Krabi province.

He was discovered lifeless in his room later on Satuday afternoon, November 23, when staff went to check on him after he failed to turn up for lunch.

They knocked on his door, only to find the room unlocked and Thomas lying dead next to his bed.

Gruesome photos show Thomas lying on the blood-soaked floor next to a shattered drinking glass. He reportedly bled out from a deep cut on his right upper arm believed to have severed a major artery.

Officers said there were no signs of a struggle, and all of his belongings - including his phone, laptop, and documents - were untouched.

Police Colonel Jetsada Sangsuree, superintendent of Aonang Police Station, said: ‘The foreigner suffered from depression and was receiving treatment here as confirmed by the doctor's certificate he had.

‘Before the incident, he sneaked out to have a drink, which is prohibited by the resort.

‘We believe that his death was caused by self-harm or an accident because there was only a single wound, and at the scene there was no other object that could have harmed him apart from the broken glass.

‘We do not believe it was a murder.'

A hotel employee said the resort also operates as a mental health treatment facility run by a therapist.

They said: ‘The deceased had checked in alone on November 13 to receive treatment for depression, and the staff had been taking good care of him, ensuring he did not go out.

'But on the day of the incident, he secretly went out to drink alcohol by himself and returned at around midnight.

‘At noon, on the day the body was found, staff went to knock on his door to call him for lunch, but there was no response.

‘The door was not locked, which seemed unusual. When the staff opened it to check, he was found lying dead in a pool of blood.'

Thomas was believed to have been dead for at least eight hours. His body was taken to a hospital as authorities coordinated with the US Embassy to notify his family.