One local defence volunteer died after gunmen armed with assault rifles opened fire from a passing pickup truck at a residential area in Yi-ngo district of Narathiwat, one of three mainly Muslim provinces near the Malaysian border.

Five minutes after the shooting, a powerful bomb planted in a nearby vehicle exploded, killing a villager and wounding 19 others.

Police said the bomb, which destroyed the vehicle and damaged nearby buildings, was triggered by a mobile phone as the assailants fled.

The attack was the latest in a recent upsurge of violence in the deep south, where more than 3,000 people have been killed in a separatist rebellion which resurfaced in 2004 after more than a decade of relative calm.

A teacher was shot dead on Saturday and five people were killed, among them two army rangers, in four separate attacks on Friday in Pattani province.

No credible group has claimed responsibility for any of the attacks in the region, which was a Muslim sultanate annexed by predominantly Buddhist Thailand a century ago. -- REUTERS