The former ambassador to Denmark found dead in a toilet in a house in Bangkok had been fatally stabbed, police said.

A forensic examination of the body found on Sunday morning revealed that he had been stabbed three times in the chest, police said.

The body of Vichit Chitvimarn, 63, was found in a toilet on the second floor of a three-storey house in Bangkok's Chatuchak district.

Police said three stab wounds were found in the chest of the former diplomat. In an examination of a box containing five kitchen knives in the kitchen on the first floor, forensic police found blood stains on two of them.

The first and second floors of the house were found to have been ransacked.

Footage from security cameras in the house was being examined.

A source said that normally Vichit lived alone but witnesses told police that before his death, Vichit had been with his step-child, 17, the biological child of his construction contractor. Police detained the teenager for questioning.

Police said they would summon two boys – 14 and 17 years old – for questioning on suspicion that they might be involved in the murder.