Villagers found Yao's severed head beside the Ban Kaena-Ban Tanyongpao road yesterday morning and reported it to the local authorities.

When officials arrived at the scene in their vehicles a bomb exploded. No one was injured.

Police later found a two-metre wide crater, three metres from Yao's head.

Among the shrapnel police found pieces of a gas cylinder and 50 metres of electric wire that led off the road to a forested area.

Officials also found a leaflet saying: "All military must leave this region. Otherwise an innocent will be killed every week."

Yao was believed to be the 20th victim of decapitation since the new wave of violence broke out in the three southernmost provinces in January 2004.

Separately but in the same district, Amphon Makkaewsong, 36, was critically injured in a drive-by shooting. Amphon and his wife Thiripan were travelling on a motorcycle when two gunmen on another motorcycle opened fire at them with a pistol. None of the bullets hit Thiripan.

Meanwhile in Yala's Than To district a bomb hidden in a food stall exploded injuring a police officer. Police received reports of a suspect package and went to investigate when the explosion occurred. The shrapnel hit Senior Sgt-Major Samut Pongkrapan in the right eye.

Police believe Muslim insurgents are behind all the attacks. More than 1,700 people have died in bombings and shootings in the region over the past two years and nine months.

The Nation