BANGKOK, THAILAND — On Wednesday, Thai authorities disclosed that cyanide poisoning is suspected in the deaths of six individuals, comprising three Vietnamese men and three Vietnamese women, who were found deceased at a luxury hotel in Bangkok. Preliminary autopsy results revealed traces of cyanide in the victims, prompting an extensive investigation into the circumstances of their demise.

Bangkok Police Lt. Gen. Thiti Sangsawang confirmed that among the deceased were two individuals with dual American and Vietnamese nationality, while the remaining four were Vietnamese nationals. The victims, aged between 37 and 56, were discovered on Tuesday by a hotel maid who noticed their absence when they failed to check out. The room, located at the Grand Hyatt Erawan, was found locked from the inside, implying that the victims might have been confined to the room prior to their deaths.

Initial findings from the investigation indicate that cyanide residues were detected in the victims' teacups, a tea flask, and in the bloodstream of one of the deceased. Despite the presence of cyanide, there were no visible signs of a struggle within the room. This absence of disturbance has led investigators to suspect a deliberate act rather than an accidental poisoning. A comprehensive autopsy report is expected to be released on Thursday, which may offer further insights into the exact cause of death.

In response to the incident, Thai Prime Minister Srettha Thavisin reported that both the United States and Vietnamese embassies have been notified. The Federal Bureau of Investigation (FBI) has been enlisted to assist with the investigation, underscoring the international implications of the case.

The victims were last seen alive on Monday afternoon when hotel staff delivered food and beverages to their room. Surveillance footage captured the six individuals entering the room and closing the door behind them. Their absence was noted the following day when they did not check out as expected, leading to the discovery of their bodies by the maid.

Investigators have uncovered that four of the victims were involved in a joint financial investment aimed at establishing a hospital in Japan. There are indications that a financial dispute related to this investment may have served as a motive for the poisoning. Noppasin Punsawat, Bangkok’s deputy police chief, noted that the personal nature of the case is unlikely to affect an upcoming conference with Russian Energy Minister Sergei Tsivilev, scheduled to be held at the hotel.

Lt. Gen. Trairong Piwpan, head of the forensic division of the Thai police, dismissed the possibility of a mass suicide. He pointed out that the victims had planned activities with guides and drivers, and the spatial arrangement of the bodies within the room suggests that they had not intentionally consumed poison in a coordinated manner to end their lives.

The case bears a resemblance to a previous high-profile incident in Thailand involving Sararat Rangsiwuthaporn, also known as “Am Cyanide.” In 2023, Rangsiwuthaporn was charged with using cyanide to poison at least 15 individuals over several years. Her actions, which targeted people to whom she owed money, established her as Thailand’s most notorious serial killer and the country’s first female serial killer.

The investigation into the deaths at the Grand Hyatt Erawan is ongoing, with authorities diligently working to uncover the motives and methods behind this tragic event.