Police said they have found evidence that four Taiwanese men and a Thai woman allegedly murdered another Taiwanese man whose body was found in a deserted stall near Suvarnabhumi airport on Sunday.
All suspects fled to Cambodia on Sunday evening, police said yesterday.
Pol Col Napatpong Supaporn, immigration chief in Sa Kaeo province, said detectives in Samut Prakan asked immigration police in Sa Kaeo on Sunday evening to keep watch for the five suspects who allegedly murdered Taiwanese national Shih Mou Chiang, 44, on Sunday.
Pol Col Napatpong said security camera recordings showed the five arriving in Sa Kaeo in a van at about 4pm on Sunday and using their passport to cross to Poipet in Cambodia at the Aranyaprathet checkpoint at about 6pm that day. Immigration police did not stop them as, at the time, there was no warrant out for their arrest, he said.
Sa Kaeo detectives learnt that the suspects visited a casino in Poipet at about 7.30pm, and at about 9pm, they hired a taxi and headed for Phnom Penh. Investigators are awaiting information from Cambodian authorities on whether the suspects have left Cambodia.
Police sources said the victim was shot repeatedly in the head at a house in the Lat Plakhao area of Lat Phrao district in Bangkok. The house is owned by a Thai national who now lives in Taiwan and was rented by the Thai woman who is among the five suspects about two months ago.
Witnesses said a Thai woman in her 20s might be the girlfriend of the murdered man. Young people of Thai and Chinese appearance regularly partied at the house, and they arrived and left in luxury cars. The victim, Shih, had allegedly fled Taiwan to avoid arrest for robbery and illegal arms possession.
On Saturday, he allegedly stole a white Toyota Yaris car in Pattaya. It was found abandoned on Ratchadaphisek Road in Bangkok at about 12.10am on Sunday. Shih arrived at the rented house in Lat Plakhao on a motorcycle at about 2am.
Three of the four Taiwanese suspects arrived at the Suvarnabhumi airport at about 2.30am, while the fourth suspect was already in Thailand. The four suspects were 25-42 years old.
At 3.12am, the suspects arrived at the house by taxi. Shortly afterwards, neighbours heard gunshots. At 4.51am a red Mazda car was seen leaving the housing estate.
At 7.30am on Sunday, the car reached Bang Phli district of Samut Prakan. It entered an alley near a waste disposal facility for Suvarnabhumi airport. Police believed the car was used to carry the victim's body, which was then dumped in a deserted food stall near the airport.
The red Mazda was later found abandoned not far away. Inside it, police found 500 grammes of ketamine, cleaning fluid, a bloodstained cloth and an empty pistol box.
Police investigations are continuing.