The family of a volunteer taxi driver shot dead on Koh Samui has sought witness protection from the Ministry of Justice.
Relatives of Sikkharin Phromcharoen, 31, fled Surat Thani with more than 10 family members, claiming they feared retaliation from influential local groups allegedly linked to the attack.
Sikkharin, known on Koh Samui for providing free transport to pregnant women, elderly residents, disabled people and poor families, was beaten and shot dead on May 24 in an alleged dispute involving illegal black-plate taxi drivers.
His wife, Onchuma, appealed for justice through the Sai Mai Tong Rod (Survive) Facebook page and the ministry's Rights and Liberties Protection Department, indicating the family no longer felt safe in the area.
She said the conflict stemmed from disputes over passenger pick-up zones after her husband parked in an area claimed by rival drivers.
A local mediator had previously attempted to resolve the dispute and the family believed tensions had ended before the fatal attack.
Ms Onchuma said police initially informed the family that surveillance camera footage was too unclear to identify the attackers. She later obtained video footage recorded by a foreign tourist and submitted it to investigators.
She also claimed residents were too frightened to provide information because of fears over the suspects' influence. The family later moved to Bangkok after strangers contacted relatives and attempted to arrange meetings.
Relatives have yet to collect Sikkharin's body for religious rites because of continuing safety concerns.
Provincial Police Region 8 said investigators had sought several arrest warrants linked to the case. Officers have detained one suspect while continuing efforts to arrest others involved.
Police later identified the suspect as Jatupol Ruangkong, 42, who on Wednesday surrendered to officers at Bo Phut police station after a warrant was issued by Koh Samui Provincial Court.
He faces charges including premeditated murder and illegal possession and carrying of firearms.
Mr Jatupol denied involvement in the assault and shooting, although he admitted knocking on the victim's car window before the attack.
He said he worked as a security guard at a nearby nightclub and claimed several men confronted the victim before gunshots were fired.
Police are still seeking suspects.
