The five were named as Watcharapol Naksen, 29; Khomsan Chaisom, 22; Praiwan Orakul, 39; Loatian man Pudsa Xaywongsa, 39; and Loatian woman Waikham Suwantong, 27.

Using two pickup trucks and one car, the group allegedly smuggled the marijuana from Laos into Thailand via Nong Khai province before passing through central Thailand with the aim of reaching the deep South.

However, police had traced them to Tambon Nong Bua in Pattana Nikhom where they carried out a swoop and discovered 500 blocks of dried marijuana in one of the trucks.

NSB commissioner Pol Maj-General Sommai Kongwisaisuk said on Monday that the suspects had reportedly confessed to the crime.

He said the seized marijuana was of a premium grade and well-packed in vacuum bags with silica gel beads. One leaf-only block weighing about 900 grams and marked “PX” is reportedly worth up to Bt100,000 because it could be used in cancer therapy, Sommai added.