Pattani, Thailand  - Suspected separatists blew up a Thai army truck Monday, killing one soldier and wounding six others, as Thai Prime Minister Abhisit Vejajjiva was in Malaysia discussing deteriorating security in the majority Muslim deep South.

Insurgents at 6 am detonated a bomb planted on a road in Ru So district of Narathiwat province, under an army pickup truck escorting teachers to school.

The explosion killed one soldier, injured six others and left a hole three metres wide and one metre deep in the road, Ru So Police Colonel Piyawat Chalermsri said.

In neighbouring Yala province, in Bannang Saa district, 720 kilometres south of Bangkok, separatists also shot dead a Muslim rubber tapper. At least three people were killed in the troubled region over the weekend.

In the past five and a half years more than 3,500 people have died in escalating violence in Thailand's three majority-Muslim provinces neighbouring Malaysia.

The area comprised the independence Islamic sultanate of Pattani more than 200 years ago, before being conquered by Bangkok.

With closer cultural, religious and linguistic ties to neighbouring Malaysia, the deep-South has been the scene of a long-simmering separate struggle that took a turn for the worse in January, 2004, when Muslim militants attacked an army depot, killing four soldiers and taking 300 war weapons.

Army reprisals on the insurgents further antagonized the local population against Thailand's Bangkok-based government.

Thai Prime Minister Abhisit paid a one-day visit to Malaysia Monday. He was scheduled to hold bilateral talks with Malaysian premier Najib Razak during which the two leaders were expected to discuss the state of security in the troubled southern Thai region, with the issue of dual nationality being the focus of talks.

Thai authorities have long claimed that Muslim insurgents from the south who also hold Malaysian nationality often flee across the border to the predominantly Muslim nation.

The trip marks Abhisit's first official visit to Malaysia since becoming prime minister on December 17, and he is the first foreign government leader to visit since Najib was appointed prime minister on April 3.(dpa)