Narcotics suppression police raided the building in Tachilek province, opposite Mae Sai in Chiang Rai, and arrested three men aged 27, 35 and 52 and a 15-year-old girl.

As well as the ya ba (methamphetamine) contained in 85 sacks, they found four sacks of ecstasy, eight kilograms of heroin and 500 grams of crystal meth, commonly known as ice.

Also seized were 24 gallons of a base chemical for making drugs, three pickup trucks, three shotguns, a tablet press, scales, logo stamps and packaging materials.