Six people who died in a luxury hotel suite in Thailand were poisoned by drinks laced with cyanide, police have said.
Police suspect that one of the dead was behind the poisoning and was driven by crushing debt.
The six deceased were found dead by housekeepers at the Grand Hyatt Erawan hotel in the Thai capital Bangkok late on Tuesday.
Investigators believe they had been dead for 24 hours by then.
Two of the six had loaned “tens of millions Thai baht” to another of the deceased for investment purposes, authorities said. Ten million baht is worth nearly $280,000 (£215,000).
Confusion and mystery had earlier surrounded the grim discovery of the bodies, with local reports initially suggesting there had been a shooting. Police later dismissed these reports.
A clearer picture is emerging now of what might have happened.
In a press conference on Wednesday, Deputy Bangkok police chief Gen Noppassin Poonsawat said the group had checked into the hotel separately and were assigned five rooms – four on the seventh floor, and one on the fifth.
On Monday, the group had all made their way to the room on the fifth floor.
Two of the victims, Sherine Chong, 56, and Dang Hung Van, 55, are American citizens.
The other four were Vietnamese nationals Thi Nguyen Phuong, 46, her husband Hong Pham Thanh, 49, Thi Nguyen Phuong Lan, 47, and Dinh Tran Phu, 37.
The group ordered food and tea, which was delivered to the room around 14:00 local time and received by Ms Chong.
According to the deputy police chief, a waiter offered to make tea for the guests but Ms Chong refused this. The waiter recalled that she “spoke very little and was visibly under stress”, authorities said.
The waiter later left the room – no one else is believed to have entered the room apart from the six inside. Police say there were no signs of a struggle or a robbery.
Police later found traces of cyanide in all six tea cups.
Relatives interviewed by the police said the couple, Thi Nguyen Phuong and Hong Pham Thanh, owned a road construction business and had given money to Ms Chong to invest in a hospital building project in Japan.
Police suspect that Mr Dinh, a make-up artist based in Da Nang, Vietnam whom police suspect had also been “duped” into making an investment.
Mr Dinh’s mother told the BBC that he had travelled to Thailand on Friday and had called home Sunday to say he had to extend his stay – that was the last his family had heard from him.