Four immigration officers accused of the abduction and crypto extortion of a Chinese man and his Thai interpreter have been suspended from the police force pending further investigation.
Police investigators have also given out their names.
Additional details were released on Wednesday by national police chief Pol Gen Damrongsak Kittiprapas and deputy national police chief Pol Gen Surachate Hakparn.
Arrest warrants have been issued for the four accused immigration officers.
The Chinese man, who has not been named, and his 38-year-old interpreter Namsee Sae Lee filed a complaint with Din Daeng police on March 20.
They said a group of men abducted them from a house in Din Daeng area and took them in a car to a house in Soi Prachasongkroh 2, also in Din Daeng area, on March 10.
The men demanded payment for their release, paid in USDT, the tether stablecoin pegged to the US dollar. The amount paid was reported then to have been 30,000 USDT, worth about one million baht. Subsequent reports in Thai media put the amount as high as 10 million baht.
The national police chief said on Wednesday he had ordered the investigation accelerated. It was a serious case with alleged involvement of state officials.
Pol Gen Damrongsak said the two victims and a Chinese friend were going to a house at Soi Trakulsuk in Din Daeng district. A group of five men in three cars had parked in front of the house. The men said they were police and asked to see their documents.
The officers then asked the Chinese man and his interpreter to get in one of the cars, which would go to the Chaeng Wattana government complex.
Inside the car, the police allegedly tried to negotiate for the pair's release through the Chinese friend, initially demanding payment of 10 million baht, to be made in tether coins. They drove around Chaeng Wattana area while the Chinese friend transferred an amount to them. The victims were later freed at Chaeng Wattana government complex, the national police chief said.
He did not confirm how much was paid.
Police questioning of the victims led to the obtaining of arrest warrants for the four immigration officers, Pol Gen Damrongsak said.
He confirmed the warrants were for Pol Maj Sorawit Inlab, a police inspector at Immigration Bureau division 1, Pol Maj Jiraphat Boonnam, also a police inspector at division 1, Pol Lt Suriya Rukkhachart, a deputy investigator, and Pol Snr Sgt Maj Peerasak Yimpaiboon.
The four faced charges that included colluding in illegal detention, depriving others of their freedom, coercion with threats to life or body, and abuse of authority, he said.
Around 11.45pm on Tuesday, officers from the Immigration division 1 escorted three of the four accused officers to Din Daeng police station - police inspector Pol Maj Sorawit Inlab, Pol Lt Suriya Rukkhachart and Pol Snr Sgt Maj Peerasak Yimpaiboon.
During questioning, they denied any involvement in the abduction. They were due to appear in court on Wednesday, when investigators would seek to detain them for another 12 days.
Pol Gen Surachate said on Wednesday the fourth accused officer, Pol Maj Jiraphat Boonnam, remained at large. His whereabouts were unknown but he expected the man would turn himself in soon.
He had ordered investigators to look into the past conduct of the four accused officers, and whether complaints had been made against them. If they were guilty, it was unlikely to have been the first time they committed such an offence, Pol Gen Surachate said.
The investigation was being extended to include another suspect, also a Thai national, and investigators would apply for an arrest warrant, Pol Gen Surachate. He vowed not to spare any officers found involved in the case.