A bag containing 100,000 methemphetamine pills was found by villagers on a roadside in Muang district of Chiang Rai province on Saturday night, police said.
The villagers found the bag in a bush near Ban Thasai village near Ban Thasai School in Muang disrict and informed the police on Sunday morning.
A team of police went to the spot and found 100,000 speed pills in the bag.
Pol Col Phumpanya Navatrakulpisut, chief of Muang district police, said he believed the bag of drugs was intentionally dumped in the bush by drug traffickers who planned to pick it up later.
Police had earlier found 700,000 methamphetamine pills dumped in a similar manner in tambon Mae Khao Tom of Chiang Rai's Muang district.