A suspected drug trafficker was shot and killed early Wednesday in a clash with police in Saraburi province while 30 others were rounded up at a "thank-you" party in Nakhon Ratchasima's Pak Chong district.
Almost simultaneously, anti-narcotics authorities launched pre-dawn raids at 27 locations in Bangkok, Samut Prakan and Nonthaburi, seized 6kg of crystal methamphetamine, or ice, 80,000 methamphetamine pills and several firearms.
Rewat Klinkesorn, commissioner of the Narcotics Suppression Bureau (NSB), said the raids were part of "Operation Triple Night" targeting the network of major drug suspect Sadayu Lueangpradapjai.
Mr Sadayu, known to be an amateur sharpshooter, is said to run a car racing gang called Nakaoka. Members of the gang are allegedly recruited to be couriers.
He said authorities had followed the activities of some of the suspects and learned a major drug gang was throwing a seminar and "thank-you" party for dozens of alleged drug dealers at a resort in Khao Yai national park in Pak Chong.
More than 100 officers were brought in to break up the party, which was said to be in its third night, and at least eight of the party-goers had arrest warrants against them for drug-related offences, according to Pol Lt Gen Rewat.
He said as authorities moved in, some suspects managed to get away in four vehicles heading to Bangkok via Mittraphap Road. Police gave chase and one of the suspects' cars came to a halt in the middle of the road when it reached the 6km marker in Saraburi's Kaeng Khoi district.
As the car stopped, a gunfight broke out in which a suspect identified as Surasak Boonthap was killed and police officer Tiwapong Pluto was seriously wounded, sustaining bullet wounds to the back. He was admitted to the Police General Hospital in Bangkok and his condition remains critical.
Two other suspects fled from the car, but one, Tawichart Kanchanakul, was captured.
According to Pol Lt Gen Rewat, the other getaway cars headed to Bangkok and one was found abandoned in Nonthaburi's Bang Bua Thong district.
Back at the Khao Yai resort, authorities rounded up about 30 suspects who all tested positive for drugs. They were detained pending further investigation into their connection to the drug trafficking ring.
The NSB commissioner said another police team raided a house in Nonthaburi's Bang Yai district owned by Mr Sadayu and found his 23-year-old girlfriend, Pornthiwa Boonthap, who denied any involvement in her boyfriend's business.
At the house, police found some ketamine and ecstasy pills. The search also uncovered and seized three guns. Some bank account information was also taken for further investigation. He said police later arrested Wachirapat In-ngern, an alleged member of Mr Sadayu's network, at an apartment, also in Bang Yai district, and confiscated 6kg of ice and 80,000 methamphetamine pills.
Meanwhile, officials from the Central Investigation Bureau on Wednesday raided 14 locations in five provinces and arrested six people as part of a crackdown on "dark influences", said Thitirat Nongharnpitak, the bureau's commissioner.
Most of the 14 targets were the houses of tambon administrative organisation heads and mayors. Confiscated for further investigation were 13 guns, 110 rounds of ammunition, nine firearm registration papers, information regarding 14 bank accounts, five land ownership documents and 30 car registration documents, he said.