Four soldiers killed in ambush in Thai south

"The soldiers were riding motorcycles on patrol when militants ambushed them and robbed them of their machine guns," police Lieutenant Colonel Mustorpha Mani told AFP by telephone.

They were patrolling a stretch of road near Chakwua village in Yala province, in advance of a convoy of teachers, when they were attacked around 2:30 pm, he said.

Teachers and schools, seen by militants as a symbol of Bangkok's influence, are frequent targets of shootings, bombings and arson attacks. Armed police and soldiers escort teachers to and from class every day.

After the ambush, the militants set tyres ablaze, dropped spikes and hauled logs onto the road to prevent security forces from chasing them, army Lieutenant General Adul Seangsingkoae said.

Adul said he had ordered 500 troops into the area.

Earlier Tuesday a Muslim schoolteacher was shot dead by suspected Islamic insurgents in neighbouring Pattani province, police said.

Surasen Mama, 30, a teacher at Prasarnwittaya school, was killed when suspected militants riddled his car with bullets as he drove to work.

Their deaths came four days after two police officers were killed in a bombing as they escorted teachers to school in neighbouring Narathiwat province, and a week after two marines were taken hostage and brutally beaten to death.

The 18-hour hostage-taking last week captured the nation's attention, drawing royal condolences for their families and a vow from Prime Minister Thaksin Shinawatra to hunt down the "beasts" who killed them.

Amid the violence, Queen Sirikit began her annual retreat in the south, accompanied by her two daughters Princess Maha Chakri Sirindhorn and Princess Chulabhorn.