A bomb blast at a village checkpoint in Thailand's deep south killed four people and wounded four others, police said on Friday, in the latest deadly attack to strike the insurgency-plagued region.

The bomb exploded late Thursday evening in Khok Pho district of Pattani, one of three Muslim dominated provinces where insurgents are fighting for greater autonomy.

Police Colonel Tanongsak Wansupha, commander of Pattani police, said the bomb was planted by insurgents, though, as with most attacks in the region, there was no claim of responsibility.

"The culprits placed a bomb under a chair at the checkpoint killing four people," said Tanongsak.

"This attack was to disrupt stir unrest."

Since 2004, more than 6,500 people have been killed in the sporadic violence in Yala, Pattani and Narathiwat, all provinces bordering Malaysia.

Thailand is a Buddhist-majority country but the south is Muslim-dominated and resistance to Buddhist rule has existed for decades.

It has occasionally spilled into nearby Songkhla province, thronged by tourists from neighbouringMalaysia. The provinces were once part of a Malay Muslim sultanate until the area was annexed by Thailand in 1902.

Shortly after taking power in a 2004 coup, Thailand's ruling junta vowed to bring peace to the south within a year.

It has made contact with some rebel leaders but talks aimed at brokering peace between insurgent groups and the Thai government facilitated by Malaysia have largely stalled due to internal discord within rebel ranks and the Thai military, as well as scepticism on both sides.