Police have arrested local officials and are looking for other people allegedly involved in the deaths of many Rohingya people found buried in Songkhla province.
The suspects already in custody were identified as Asan Inthathanoo, 42, a tambon Padang Besar municipal councillor; Ror-en Sonyalae, 41, assistant headman of Ban Talo village; Alee Lamoh, 47, assistant village head, and Zaw Niang Anu, a 40-year-old Myanmar man.
Mr Asan and Mr Ror-en allegedly provided detention camps with supplies and Mr Alee was suspected of guarding the camps. They denied all charges at a police press conference in Songkhla on Monday.
Sawniang Anu had been detained in Nakhon Si Thammarat province in another case for fraud and kidnapping for ransom of Rohingya people. The four were charged with human trafficking, detention and abduction for ransom.
Police sought arrest warrants for another four suspects linked to the Rohingya detention camps in Songkhla.
They are Prasit Lemleh, deputy mayor of tambon Padang Besar; Yalee Khrem, head of Ban Talo village; Pakapol Benlateh, 47; and Charoen Thongtaeng, 45.
Besides, a police sub-lieutenant and a sergeant major of tambon Padang Besar were transferred to inactive posts as they had been responsible for the area where the detention camps and Rohingya bodies were found and might have been implicated in the crime.
National police chief Somyot Pumpunmuang said on Monday responsible authorities were taking serious action on the case.
"The prime minister (Gen Prayut Chan-o-cha) just phoned me again and ordered me to be there to follow up on the case. All people involved will be arrested and no one will be spared. This issue is causing a great problem to the country," the national police chief said before boarding a flight to Songkhla on Monday morning.
He also said that police would seek warrants for the arrest of many more suspects.
Senior national-level officials were heading for the South after the discovery of many detention camps, graves and bodies of Rohingya migrants on Khao Kaew mountain in tambon Padang Besar of Sadao district near the Thai-Malaysian border on Friday.
The human trafficking case was an illegal transnational business and the detention camps were near a border patrol police base, Pol Gen Somyot said. He would coordinate with authorities in Malaysia and Myanmar for legal action and investigation into the case.
The human trafficking gang involved Thai, Myanmar and Malaysian people, he said.
The detention camps showed that a large number of Rohingya people had been transported per trip and the business had continued for 3-4 years, he said.
Forensic examinations of the bodies of 26 Rohingya people, 25 males and one female, unearthed in Padang Besar would determine if they died of illnesses or physical assault.
Initial examination pointed to illnesses and starvation as the causes of death, Pol Gen Somyot said.
Detectives said off the record that four more people would face arrest warrants.
They include an administrative official who is believed to be the ringleader. The others were local politicians and community leaders in tambon Padang Besar, as well as some Rohingya people, the sources said, adding that they had already fled.
Army chief and Deputy Defence Minister Udomdej Sitabutr was also visiting Songkhla and Ranong provinces to investigate the human trafficking case.
He said he would also go to Ranong, the entry point of most Rohingya migrants. He gave an assurance any government officials found to be involved would face harsh action.
It was reported that migrants from Rakhine state of Myanmar and Bangladesh were used as forced labour at such detention camps and kept until ransoms were paid by their relatives, both on their homeland and in Malaysia. Some of the migrants were kidnapped from their homeland.