More than 880 people have been killed since January last year when a resurgent separatist movement in the country's three predominantly Muslim provinces bordering Malaysia -- Pattani, Yala and Narathiwat -- resumed a campaign of bombings and killings.
Police Capt. Thaweeksak Thengworawit said the gunmen stormed the rented house in Pattani late Monday and opened fire on the praying men, before speeding away.
Thaweeksak said the killers left a note with the bodies that read: "All of Allah's fighters stand up and fight to protect the religion and liberate Pattani ... Those who cooperate or spy for the enemy or don't come to us, we will come to get you."
Police said they believed the attack and letter were intended to persuade Muslims to support the separatist cause and intimidate those who support the central government in the Buddhist-dominated kingdom.
On Tuesday, a 10-kilogram bomb triggered by mobile phone exploded in the parking lot of a bank in Narathiwat province, destroying part of the building and several vehicles but causing no injuries. It was the second bomb blast outside a Narathiwat bank in less than two weeks.
A separatist movement that first emerged in the early 1970s but dwindled over the next two decades has reappeared since Prime Minister Thaksin Shinawatra came to power in 2001.
Political opponents and many analysts blame the growing violence on his mishandling of the delicate situation in the south and an ineffective and corrupt police force.
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