A combined police and military rangers force clashed with a gang of armed drug traffickers in Bung Kan province in the early hours of yesterday.
About 200kg of compressed cannabis with a street value of 6 million baht was seized after the clash.
Despite an intense gun battle which lasted about five minutes, no one was hurt, said Bung Kan provincial police chief Chaiyaporn Panich-attra.
Eight drug traffickers, three of them armed, were confronted by the combined force on Highway 212 in Ban Non Sa in Bung Khong Long district.
Authorities spotted the men carrying bags and walking up the bank of the Mekong River.
When ordered to identify themselves, the gunmen opened fire, Pol Maj Gen Chaiyaporn said.
All of the drug smugglers and their armed guards escaped but left behind the 200kg of cannabis.
In Chiang Rai, provincial governor Pongsak Wangsamoe told a press conference yesterday that a special task force on drug suppression had seized 450,000 tablets of methamphetamine and a motorcycle.
They were seized from two drug suspects who escaped.
The operation was carried out in Ban Bo Thong in Chiang Rai's Muang district, where the taskforce had set up a roadside security checkpoint on Thursday night.