Forensic officers have collected DNA samples from the dead to help in the identification process, said Pol Lt Col Kittisak Nuphueng, a Phuket forensic inspector.
The DNA sample and evidence collection was proceeding yesterday as forensic officials at the Institute of Forensic Medicine at the Police General Hospital in Bangkok were trying to establish the identities of the badly-burned bodies of the four victims.
Pol Lt Col Kittisak said the two Thais and a British man have provided their own DNA samples because they fear the victims are their biological relatives. The French individual has provided material evidence.
He said the samples will be sent to the Institute of Forensic Medicine for examination. The testing process takes about 24 hours.
Booncherd Butkho, 62, said that he is convinced his daughter, Duangporn, is one of the victims after speaking with one of her friends who escaped the fire.
"She went to the toilet [before the fire started]. That was when her friends last saw her," he said.
Mr Booncherd has provided DNA samples to police.
Joseph Tzouvanni, 26, a British national, yesterday asked police to collect his DNA samples for testing.
He flew in on Saturday, a day after being informed that his 24-year-old brother, Michael Pio Tzouvanni, had been missing since the fire.
Mr Tzouvanni said he inspected his brother's hotel room and everything was packed. His brother was scheduled to leave Phuket yesterday. Passakorn Jirapattanasophon, a friend of the younger Mr Tzouvanni, said that his friend had metal implants in both knees.
Pol Lt Col Kittisak said that if others suspect their relatives might have been killed in the fire they may ask police to collect DNA samples for examination.
In Bangkok, Pol Lt Gen Charamporn Suramanee, assistant national police chief, said yesterday that initial examinations showed that two of the victims were Asian females and the other two were Caucasian males.
The findings also suggest that they died from suffocation.