Soldiers protect about 100 Muslims gathered in Yaha district of Yala to vent their anger over continuing violence by insurgents.

The handbooks came out one day after a powerful bomb blew off the left leg and left arm of the deputy commander of Narathiwat Provincial Police, Colonel Nopadol Puerksomon, who was still in a critical condition yesterday.

Nopadol was leading a team to investigate one of seven bomb sites on Wednesday when he stepped on a booby-trap, triggering a powerful explosion.

This was a different tactic as bombs are usually detonated remotely by mobile phone. But because the authorities usually cut off mobile phone signals, the insurgents have opted for booby-traps to trigger the devices.

Several intelligence sources told The Nation that although the bomb that nearly killed Nopadon was home-made, using PVC pipes and ammonium nitrate, it was deemed a "progressive" move by the militants.

The new tactic has prompted Isoc to respond quickly in prevent similar incidents.

In other news, suspected militants burnt down a public school in Narathiwat's Bannang Sata district and shot dead two local Muslims in separate incidents.

Police said a 44-year-old villager was gunned down late on Wednesday in a drive-by shooting while riding a motorcycle in Yala, while in Narathiwat a 52-year-old local was shot dead by three gunmen near his motorcycle.

Meanwhile, US-based Human Rights Watch (HRW) expressed concern over what they said was the government's "growing reliance" on authority-backed militias to combat the increasingly violent insurgency in the restive region.

On April 9, government-backed Village Defence Volunteers in Yala's Tambon Kuern Banglang fired on a crowd of Muslim funeral-goers, killing four students and injuring at least five people.

On March 9, a group of rangers, an Army-trained and equipped paramilitary force, fired on a civilian vehicle in Ban Ta Seh village in Yala, killing a 15-year-old student and seriously wounding his brother-in-law.

"These cases of deadly use of force show how dangerous it is for the government to arm and deploy poorly trained militia forces," said Brad Adams, Asia director for Human Rights Watch.

While acknowledging that villagers in the troubled region had the right to defend themselves, Adams noted: "We've seen examples from around the world of how ill-disciplined volunteer militias use weapons improperly and set off a vicious cycle of reprisal attacks against civilians."

HRW also criticised the government for allowing these paramilitary forces immunity from justice.

"Thai authorities have a duty to discipline and, where necessary, prosecute Army rangers and any other irregular forces that commit abuses," Adams said.

"It should start by conducting a credible and transparent investigation into the killings by paramilitary forces in Ban Pakdi and Ban Ta Seh."

Adams said the Thai government must understand that any attempt to cover up the misconduct of its security units or to protect them from criminal responsibility could set off a cycle of killings and reprisals.

HRW also urged the government to instruct its forces to comply with the United Nation's basic principles on the use of force and firearms by law-enforcement officials.