Suspected Islamic militants (search) beheaded a Buddhist man in Thailand's (search) tumultuous south, the second such killing in retaliation for the deaths of 85 Muslims at the hands of security forces last month, police said Tuesday.

The decapitated body of a 60-year-old laborer was found Tuesday in a hut at the rubber plantation where he worked in the village of Changpeuk in Narathiwat province, said police Lt. Boonserm Klaewatee. Officials said the man's last name was Kaew; his first name was not available.

Kaew's head, found nearby, had been slashed repeatedly, apparently by a machete, he said.

Police found four handwritten letters with the body, all of which said: "This is not enough. More will be killed in revenge for the innocents that were killed in the Tak Bai massacre (search)."

At least 85 Muslims died on Oct. 25 when security forces cracked down on a violent protest outside a police station in Narathiwat's Tak Bai district. Most of the victims suffocated or were crushed after being stacked in trucks and taken to an army camp.

Kaew is the third Buddhist man to be beheaded by suspected Muslim insurgents in southern Thailand this year, and the second in retaliation for the Tak Bai incident. The head of an assistant village leader was found last week with a similar letter.

Earlier Tuesday, masked men stormed houses in Pattani province and stole 10 shotguns, said police Maj. Gen. Thanachareon Suwanno. The government has distributed hundreds of shotguns to villages in southern Thailand, and officials fear many of the weapons may have fallen into the hands of insurgents.

"They will use these stolen guns to kill the innocent people," Prime Minister Thaksin Shinawatra told reporters Tuesday. "At least four or five innocent people have been killed every day. The lives of innocent people are in serious danger."

More than 500 guns, rocket-propelled grenades and tons of dynamite and fertilizer used for bombs have been stolen from military facilities and private companies since January.

More than 500 people have been killed this year in attacks blamed mostly on Muslim insurgents. The unrest is part of a revived Islamic insurgency that began to emerge in recent years, officials say.