A car bomb exploded killing an army officer in southern Thailand.

Sergeant Major Sainuden Dorkor was escorting a local district official when the explosive went off along a road in Narathiwat on Monday afternoon.

The grey pickup truck carrying the Riang Subdistrict Protection Volunteer Unit was sent flying by the blast at 3:30 pm local time.

Police later arrived to secure the scene, where they found the defence volunteer dead.

Nirat Pongsitthaworn, director-general of the Department of Provincial Administration, paid tribute to Sainuden and expressed condolences to his family.

He added that the department will provide compensation and assistance to his relatives.

Earlier that morning, two village officials were injured when a bomb exploded near train tracks.

The explosive went off while officers were inspecting the railway. Two men were injured by shrapnel and rushed to the Ra-Ngae Hospital for treatment.

Islamic separatist terror attacks target the three southernmost provinces of Thailand - Yala, Pattani and Narathiwat - next to the border with Mulsim neighbors Malaysia. Thai state employees and infrastructure are often hit while attacks on civilians are rare.

Officials believe the conflict dates to a deal in 1909 that the British Empire struck to incorporate the Muslim region into the Siamese mainland.

The region's culture is more similar to Malaysia and dramatically different to Buddhist Thais causing decades of tension that lead to the emergence of separatist groups fighting for independence in the 1960s.

The struggle has continued ever since with more than 7,344 people killed and 13,641 injured between January 2004 and March 2022.

The British Foreign & Commonwealth Office warns against all but essential travel to the region while Canada's government warns its nationals to 'avoid all travel' to the three provinces.