Deputy Prime Minister Chalerm Yoobamrung, in his capacity as Director of the National Command Center for Drugs (NCCD), and National Police Chief Prewpan Dhamapong jointly told a news conference of the capture of the drug suspect, identified as Nipon Mopad, 43.
Police planned to arrest Mr Nipon at home in Saraburi's Nong Khae district after investigators found that he used his house to pack the dried cannabis into boxes for shipping to the UK.
The police also found 3.5 tonnes of dried cannabis packed in boxes with a street value of about Bt51 million.
Mr Nipon told police that he was hired by a man he knew only as Mr Toss to pack the drug before delivering the packages to another man named Mr Tong. He was to be paid Bt100,000 for the packing job.
Charged with possession of drugs for sale, the suspect could lose all his assets, including his home and vehicle, if found guilty.
Meanwhile, Saraburi Highway Police stopped a pickup truck with a Bangkok registration plate when the driver attempted escape when police asked to search his vehicle.
The driver, identified as Atchariya Ponyukol, 25, had packages of marijuana weighing 648 kilos in his possession.
Mr Atchariya said that he was hired to pick up the drug in the northeastern province of Nakhon Phanom and was to deliver it to customer at a Minburi market.
He was to receive Bt35,000 for making the run, and told police he had twice previously made similar deliveries. Persons travelling in another vehicle who were thought to be involved escaped.