A white pick up truck passed the transport vehicle immediately after the explosion and three to four men in the truck sprayed bullets at the soldiers before fleeing the scene.
Five soldiers were wounded, two seriously. All were sent to hospital in Yala.
The six-wheel M35 military truck was seriously damaged in the incident, which took place on Ban Niang-Pi Sad road in Lam Mai subdistrict.
Fragments of a home made bomb estimated to have carried 3-5 kilograms of explosive material were scattered in the area.
The authorities believed the bomb was built into a bicycle and triggered by radio signal or mobile phone. The twisted remains of a bicycle was found nearby.