Acting on tip-off, police and troops staked out a border spot in Mueang Bueng Kan district and they spotted a pick-up truck driving up from the Mekong River bank at 4 am Sunday.
They found Pornchai Noneboribun, 53, behind the wheel and found 300 kgs of the drug in nine sacks.
Pornchai said he was hired to deliver the drug to Satun. He told police that Tippawal Khun-aksorn 59, and Wipassaya Hassadee, 38, were waiting in another car in Sakon Nakhon to lead his way. Police later arrested the two women.