Mukdahan Immigration Superintendent Pol Colonel Komen Suparp led officers to intervene in an incident where five men surrounded and threatening to assault truck driver Weerayuth Thanhai.
Police apprehended the three Thais - Ampol Chondee, 23, Jenpop Phahat, 28, and Theerachai Sornsungnoen, 31, and two Lao accomplices, identified only by first names as Wonchai, 22, and Kai, 24. They have been charged with putting a person in fear by threat, which is punishable with a maximum one-month jail term or a maximum Bt1,000 fine, or both.
The two Lao men were also charged with illegal stay in Thailand.
Weerayuth told police that after obtaining a border pass he was driving the truck out of the car park towards Laos when his vehicle scratched a side mirror of a truck belonging to a Thai man, Udon Sajja, resulting in an argument.
Udon accused Weerayuth of cutting in front of the queue and Weerayuth got out of his truck, holding a knife.
Udon responded by calling on his friends to back him up.
After police arrived and apprehended the five men, Udon returned to the area in a pick-up truck. In a search of his vehicle, police found seven bullets and a rifle equipped with a silencer. He was charged with having a gun and ammunition in his possession without permission and carrying the weapon without a sound reason.