Pol Snr Sgt Maj Boonsueb Chumyim, an investigation officer at Phra Nakhon Si Ayutthaya district police station, his mistress Kanchana Pinta and Amphon Sappawut, 18, were arrested separately in Ayutthaya and taken for a police press conference tyoday.
Police earlier arrested Mr Amphon and seized 2,000 speed pills from him in Bang Pa-in district. An extended investigation led to the arrest of Pol Snr Sgt Maj Boonsueb and Ms Kanchna, who were apprehended when delivering 4,000 speed pills to a police officer posing as a drug buyer at a petrol station in this central-region province.
Police later took the officer to search his house in Ang Thong province where 8,000 more methamphetamine tablets, four pistols, B231,000 cash and several bank accounts were seized.
Pol Snr Sgt Maj Boonsueb confessed to all charges. He admitted he had behaved badly and apologised to the Royal Thai Police Office and his fellow officers for tarnishing the reputation of the police force.
Pol Lt Gen Amnuay said he already signed an order to dismiss the officer from service for gross misconduct and serious violations of the law, causing damage to the police force and the country.
The officer and the two other suspects have also been charged with illegal possession of drugs with intent to sell.
An initial police investigation found that Pol Snr Sgt Maj Boonsueb, who was also a member of a drug suppression team, took drugs seized from traffickers and sold them to small dealers. The officer had also allegedly extorted money from drug traffickers.
Pol Lt Gen Amnuay said four more officers attached to the same station had allegedly colluded with the accused officer in the drug trade. He has already obtained their names and would issue warrants for arrest.