Autopsy and DNA samples suggest that four separate sets of parts of a human body found in several locations along the river in Phatum Thani and Bangkok are all from the same person, he said.

The man was 165 centimetres tall and had black hair and full set of teeth, he said. The autopsy indicated that he had undergone surgery to have his appendix removed.

There was tape on his arms, suggesting he was bound, but no contusions on his body which led them to believe he was not beaten to death, he said.

The body parts could have been chopped up with a heavy-duty saw and could have been dumped into the river in the area between Phatum Thani and Nonthaburi, which is not far way from the killing location, he added.

Police Lieutenant Colonel Chakarin Piriyachita, who is a member of the investigative team, said the man is probably not a Thai but it is possible he might be a mixed blood Asian-European. He might have been tortured before being killed, he also said. The murderers who killed him might have butchering skills, police said.

The police are continuing their investigation to determine his identity and are studying previous similar cases to compare the methods and see if it resembled any other murders.

Chakarin earlier said that relatives of missing Chinese journalist Li Xin have contacted the Chinese Embassy to Bangkok to verify whether the found dead man was him.

However his wife He Fangmei said the journalist has reappeared in mainland China and was being held by police at an undisclosed location, according to The Guardian.

Li Xin, a former journalist at the Southern Metropolis Daily newspaper, lost contact since early January as he prepared to travel from Thailand to Laos.