An American Vietnamese woman is believed to have killed five people and herself with cyanide-laced tea at a Thai hotel over an investment dispute, according to police.
The group of six — four Vietnamese nationals, and two US citizens of Vietnamese heritage — was found dead in room 502 of the luxury Grand Hyatt Erawan hotel in Bangkok on Tuesday.
The three men and three women were last seen alive when food was delivered to the room on Monday afternoon.
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Staff saw one woman receive the food, and security footage showed the rest of the group arriving one by one shortly after.
Police identified the woman as 56-year-old Sherine Chong, according to The Bangkok Post.
The victims have been identified by police as US citizen Dang Hung Van, 55, and Vietnamese nationals Nguyen Thi Phuong Lan, 47; Pham Hong Thanh, 49; Tran Dinh Phu, 37; and Nguyen Thi Phuong, 46.
Metropolitan Police Bureau deputy commissioner Police Major General Nopasilp Poonsawat said Chong ordered tea and food from room service and refused a worker’s offer to brew it for her in the room, saying she would prepare the tea herself.
Security footage showed the group — who were staying in other rooms in the same hotel — arriving at room 502 with their packed luggage.
No one was seen leaving and the door remained locked, until a maid made the grim discovery when no one checked out of the fifth-floor room the following day.
A table full of uneaten room service meals, some with plastic covers still on, was found next to several used tea cups and thermos bottles.
Traces of cyanide were found in the victims’ blood during autopsies and in the cups and thermoses found in the room, police said.
Chulalongkorn University dean of medicine Chanchai Sittipunt told reporters the team knew enough from the cyanide to determine it was likely the cause of death.
The source of the cyanide is still under investigation.
No signs of injuries or struggle were found on the bodies, which were found scattered about the hotel room, some in the living room and some in the bedroom.
Police said two of the people appeared to have tried to reach the door but collapsed before they could.
Relatives of the five killed told police there had been a dispute over debt related to an investment.
A husband and wife among the dead had invested about 10 million baht ($A400,000) with Chong and a Vietnamese woman in a construction project that had not shown any progress, police said.
They had taken legal action over the lack of progress, and the group of six was due to meet in court in two weeks, The Post reported.
Chong reportedly invited the five to meet for out-of-court negotiations, and they had checked out at 12pm on Monday when she invited them back for another round of talks in room 502.
Prime Minister Srettha Thavisin said the Vietnamese and US embassies had been contacted over the deaths.
The Grand Hyatt Erawan, operated by Erawan Group, has more than 350 rooms and is in a popular tourist district known for luxury shopping and restaurants.
– With AP
