Police said a total of 1.2 million methamphetamine tablets, or yaba, were seized from the vehicle.
Deputy chief of Police Region 5 Pol Maj Gen Chamnarn Ruadrew, said the police had been investigating a drug gang from Tak province. A checkpoint was set up on a road in Mae Tha district.
The drug smugglers drove their pickup truck through the checkpoint and later abandoned the vehicle as pursuing police closed in. When police tried to arrest them they had fought back with gunshots and police retaliated.
After they fled police found the body Noppadol Phetkeereerat, 26, a Hmong hill tribesman from Lamphun province.
In the back of the pickup, police found baskets of fruit and 12 backpacks concealed beneath them holding a total of 1.2 million yaba pills.
Pol Maj Gen Chamnarn said the gang was part of a Hmong network innvoled in smuggling drugs over the border in Chiang Rai to Chiang Mai, with the final destination in the Central region.