BANGKOK, Nov. 25 (Xinhua) -- Five suspected drug traffickers were killed in a clash with Thai army troops in Thai-Myanmar border area on Saturday night.

The slain drug suspects were among a group of about 10 heavily-armed men, who had been spotted trafficking drugs from Myanmar to Thailand's mountainous border area in Mae Sai district of Chiang Rai province, said an army source on Sunday.

A patrol squad of the Second Cavalry Regiment, attached to Pha Muang Task Force, exchanged gunfire for about 15 minutes with the unidentified, suspected drug traffickers, killing five of them.

The other suspects retreated into Myanmar's territory while no casualties on the Thai side were reported, the army source said.

Hours later, the cavalry unit cleared up the scene and found an estimated one million tablets of methamphetamine in strapped bags alongside the bodies of the gunned-down suspects.

No tourists have been allowed to pass the border area in which the clash had occurred due to security reasons while Third Army Region commander Lt. Gen. Chalongchai Chaiyakham inspected the scene on Sunday.