Pol Col Thitisan Utthanaphon, the prime suspect in a case involving the fatal torture of a drug suspect at the Nakhon Sawan's Muang police station, was arrested last night after he surrendered in Bangkok.
He was taken into custody at the Crime Suppression Division headquarters after surrendering to CSD agents in the city.
Pol Maj Gen Jirabhop Bhuridej, deputy commander of the Central Investigation Bureau, said the suspect fled to Chon Buri and police pursued him in the province before he was arrested.
Pol Col Thitisan denied extorting two million baht from the victim, saying he tortured him because he wanted to expand the investigation.
Earlier, reports claimed he had fled across the border. Police had also visited his luxury home in Bangkok hoping to find him there, without success.
The suspect contacted police and asked to surrender at the CSD headquarters, Pol Maj Gen Jirabhop said.
According to police sources, the suspect succumbed to mounting pressure from the massive police hunt for him.
Early in the day, a rumour said the suspect had surrendered to Myanmar authorities in Myawaddy, across from Thailand's Mae Sot in Tak province.
Pol Col Thitisan was suspended from the force pending an investigation, and a court warrant was issued for his arrest after a video clip posted on social media allegedly showed him in an interrogation room with a drug suspect being suffocated to death with a plastic bag over his head.
Pol Col Thitisan fled before the warrant was issued.
The clip made headlines, and sparked a storm of condemnation of the police colonel and his six subordinates, prompting Prime Minister Prayut Chan-o-cha on Tuesday to order the police to investigate.
Arrest warrants were also issued for six of Pol Col Thitisan's subordinates who were allegedly present in the interrogation room.
They have also been suspended from the police. All seven suspects have been arrested.
Pol Gen Suchart Teerasawat, head of the investigation team, said the offence was clear as shown in the video. Police investigators could verify the identities of those involved, he said, adding five of the suspects had cooperated.
He said his team had investigated why the drug suspect was taken to the Muang police station in Nakhon Sawan, but the details could not be disclosed.
There was no police record of the seizure of 100,000 meth pills on the day the drug suspect was tortured, according to local media reports.
But an autopsy was performed on the dead suspect, Pol Gen Suchart said.
Investigators were still compiling the evidence and looking into the motive to determine whether it was about extorting money or finding drugs hidden by the suspected drug dealer, he said.
The dead suspect had a record for drug possession, he said.
Chiraphong Thanapat, 24, died at Muang station in Nakhon Sawan on Aug 6. He and his wife had been arrested on a bypass road in the province.
Pol Gen Visanu Prasattongosoth, inspector-general attached to the Royal Thai Police, said all seven suspects will also be investigated for severe disciplinary violations.
They now face charges for dereliction of duty, torture and murder.
Five suspects who surrendered first were taken to court where they will now be detained for 12 days pending an investigation.