The Crime Suppression Division (CSD) has detained a key suspect in the execution-style murders of eight members of a family in Krabi as police narrow their probe.
CSD officers are questioning the suspect who is believed to "have played a role as a mastermind behind the murders", a source close to the investigation told the Bangkok Post yesterday.
He is believed to have spoken with Worayut Sanglang, 46, the head of the murdered family, who was killed in the attack, before the massacre took place.
CSD experts, who traced the usage of Worayut's mobile phone, found he talked on a phone with one of his close friends for nearly 10 minutes before he was gunned down. This piece of information led investigators to believe the man the victim spoke to might be involved in the murder.
Police identified the suspect as "a partner in a stone mill", the source said.
A conflict over a stone mill project is one of the suspected motives behind the killings. Worayut worked on behalf of Ao Luk Sila Thong Co in 2015 to contact state agencies for a concession for the stone mill construction project. The company later took over the project from Trang Phuthong Mill Limited Partnership which was given a 10-year concession in 2012 but faced opposition from residents.
The source said police suspected Worayut might have received money from project financiers in exchange for appeasing the protesters, but he failed to calm them down, which eventually sparked a conflict between him and the financiers.
Earlier, police said there might be at least seven suspects involved in the massacre in which three males and five females, including three children, were slain in their house in Ao Luk district on July 10.
One of three injured survivors said the attackers spoke with Central Plains accents. Only one attacker, who wore a balaclava, is likely to be a local, a 30-year-old woman, who narrowly escaped death, told police.
CSD investigators, led by Pol Col Phumin Poompanmuang, who is chief of the CSD's sub-division 5, are also searching for more suspects in Krabi's neighbouring province of Nakhon Si Thammarat. The officers, who believe the gunmen might be hiding there, yesterday raided some undisclosed locations, the source said.
Reportedly the gunmen, who wore army camouflage outfits, might be former soldiers.
National police chief Pol Gen Chakthip Chaijinda, during his meeting with investigators in Krabi on Thursday, assigned the DSI to search for more witnesses.
Witnesses who knew Worayut, who was also a village headman, have given accounts that may shed light on the series of events before the killings.
According to the source, one of Worayut's friends raised doubts over what he called "unusual wealth".