Police were investigating today after six American Vietnamese nationals were all found dead inside a luxury hotel room in Bangkok.

Pictures show officers outside the Grand Hyatt Erawan where the group of ethnically Asian guests were found dead. It is not yet known how they died but they are believed to have been poisoned.

Five of the dead were named by police as females Sherine Chong, Thi Nguyen Phuong and Thi Nguyen Phuong Lan. Two dead men were Dinh Tran Phu and Hung Dang Van. The sixth has not been named.

Officers said that traces of fighting were found inside the room shortly before 5:30 pm local time. Five bodies are believed to have been inside the room and one outside the door.

Police Lieutenant General Thiti Saengsang, commander of the Metropolitan Police Bureau, along with Major General Noppasin Poolsawat, deputy commander of the Metropolitan Police Bureau, were dispatched to the suspected crime scene.

They said the dead were believed to be of Vietnamese origin with American passports.

Police Lieutenant General Thiti Saengsang said: 'Hotel staff found the dead inside the room. They called the police immediately and forensic officers arrived.'