Alleged motive for cyanide poisoning that killed six at Bangkok’s Grand Hyatt hotel

A Vietnamese-born woman in the United States allegedly killed five people and herself with cyanide-laced tea at a Thai hotel following an investment dispute, police say.

The group of six people – four Vietnamese nationals and two Vietnamese-American citizens – were 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 afterward.

Police identified the woman as Sherine Chong, 56, according to the Bangkok Post.

The victims were identified by police as U.S. 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 had ordered tea and food from room service and declined an employee’s offer to prepare it for her in the room, saying she would make the tea herself.

Security footage showed the group – who were staying in other rooms at the same hotel – arriving at Room 502 with their luggage packed.

No one was seen leaving and the door remained locked, until a maid made the grim discovery when no one left the fifth-floor room the next day.

A table full of uneaten room service dishes, some with plastic lids still on the table, was found alongside several used teacups and thermos bottles.

Traces of cyanide were found in the victims’ blood during autopsies as well as in cups and thermoses found in the room, police said.

Chulalongkorn University’s medical faculty dean Chanchai Sittipunt told reporters the team knew enough about cyanide to determine it was the likely cause of death.

The source of the cyanide remains under investigation.

No signs of injury or struggle were found on the bodies, which were found scattered around the hotel room, some in the living room and others in the bedroom.

Police said two of the people appeared to have tried to reach the door but collapsed before they could do so.

Relatives of the five people killed told police there had been a dispute over a debt related to an investment.

A husband and wife among the dead had invested about 10 million baht ($400,000) with Chong and a Vietnamese woman in a construction project that had shown no progress, police said.

They have filed a lawsuit over the lack of progress, and the group of six is ​​scheduled to meet in court in two weeks, the Post reported.

Chong reportedly invited the five to meet for amicable negotiations, and they had left the hotel at 12 noon 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 about the deaths.

The Grand Hyatt Erawan, operated by the Erawan Group, has over 350 rooms and is located in a popular tourist area known for its luxury shopping and restaurants.

– With AP