KUALA LUMPUR, Sept. 1 -- A Malaysian man was arrested by Thai authorities in Sadao, Songkhla, after police found military-grade assault rifles and hundreds of rounds of ammunition in the car he was driving.

According to Harian Metro, the 46-year-old suspect was stopped at a police roadblock at about 5.35pm yesterday as part of an operation targeting drug smuggling and other security threats.

Checks on his Malaysia-registered Kia uncovered two M4 assault rifles, 300 rounds of 5.56mm ammunition, seven 5.56mm magazines, 100 rounds of.45 calibre bullets and 50 rounds of 9mm bullets.

"All the weapons and ammunition were seized as case items for further investigation," the Malay-language daily quoted a source as saying.

Thai police are stil...