The 58-year-old, whose name is being withheld until relatives are informed, was found lying on the floor next to his bed in the PL House guesthouse on Rat-U-Thit 200 Pi Rd, wearing just a shirt.
There was a large patch of blood on the sheets of the bed, and on the dead man’s arms. A scarf was tied around his right ankle.
Police noted that various items – a lamp and books – were strewn across the floor, along with a bottle of injectable medicine used to treat asthma, and a photo of the dead man with a male friend.
The noted that the man, a native of New Jersey, had bookings in the guesthouse from May 1 until next Thursday (May 15), and had prepaid with his credit card.
Although investigators tend to believe his death probably came about because of the asthma, they are also examining the possibility that there may have been a sexual angle, and they took security footage from the guesthouse to check for visitors to his room.
The United States Embassy has been informed.