Fugitive Pol Col Thitisan Utthanaphon, aka Jo Ferrari, said he wanted to extract information about more drugs from a suspect.
The former chief of the Nakhon Sawan Muang police station surrendered himself to police in Chon Buri on Thursday evening.
Police chief Gen Suwat Jangyodsuk was scheduled to hold a briefing at 9pm on the same day. At about 9.45pm, he gave an overview of the case and assured he would not protect any wrongdoer. Then he let Pol Col Thitisan phone in to take reporters' questions.
Pol Col Thitisan admitted he had used bags on Jeerapong Thanapat, a 24-year-old drug suspect, during questioning, but said the motive was not to extort money from him.
Having seen photos of around one kilogramme of crystal methamphetamine and 20,000 speed pills on Jeerapong's mobile phone, he thought it was a big case and tried to extract more information about the lot from him, he claimed.
“I intended to get the information so I can destroy the drug business and protect the people of Nakhon Sawan. I made a mistake. My subordinates just followed my order and I take sole responsibility,” he said.
The 39-year-old former policeman insisted it was the first time he treated a suspect that way and denied having been involved in corruption.
On why he used as many as six bags to cover the suspect's head, he said he did not want Jeerapong to see his face but the suspect kept trying to remove them, forcing him to also tie his hands.
After Jeerapong lost consciousness, Pol Col Thitisan said he assumed the suspect was in shock because his wife had said he usually took large quantities of narcotics and suffered from lack of sleep.
His team tried to resuscitate Jeerapong, "whose breathing was shallow and pulse was weak", and brought him to hospital.
Asked why he ordered subordinates to remove security cameras at his station, Pol Col Thitisan said he was shocked by Jeerapong's condition and had never experienced such an incident.
After talking to reporters for about 15 minutes, the reporters asked him how he felt when one of his subordinates sent the clip to the public. At this point, deputy national police chief Pol Gen Suchart Teerasawat ended the session, saying he did not want reporters’ questions to affect the case.
Pol Col Thitisan was wanted for the alleged fatal torture of Jeerapong at his Muang Nakhon Sawan police station in Nakhon Sawan province on Aug 6. Earlier, senior police said detectives had not concluded whether the death resulted from an attempt to extort money or acquire information.
Pol Col Thitisan appeared at the Crime Suppression Division in Bangkok on Thursday night and was interrogated by national police chief Pol Gen Suwat Jangyodsuk.
Pol Maj Gen Jirapop Puridet, deputy commissioner of the Central Investigation Bureau, said detectives were about to arrest Pol Col Thitisan in Chon Buri province but the suspect told police that he wanted to surrender at the CSD headquarters.
Asked about the earlier report that Pol Col Thitisan fled to Myanmar, Pol Maj Gen Ekarak Limsangkat, deputy commissioner of the Provincial Police Region 6, said that Pol Col Thitisan phoned him at 11pm on Wednesday and said he wanted to commit suicide.
He said he convinced Pol Col Thitisan to surrender and do the right thing to protect the honour of the police.
Pol Maj Gen Ekarak said Pol Col Thitisan showed up at Saen Suk police station in Chon Buri at 4pm.