At the end of the school day in southern Thailand, the children line up before being dismissed. But it is the teachers who are escorted home by armed troops.

Two motorcycle-riding soldiers head the convoy leaving a school in Chanae, in Narathiwat province, and a lorry mounted with a machine-gun brings up the rear.

An Islamist and separatist rebellion in the region has killed more than 800 people in 18 months. It is one of the world's bloodiest insurgencies and a potential breeding ground for radicals.

Earlier this month three people were killed at a tea shop down the road from I-Gross School, soon after a woman teacher was shot dead in Chanae, and there are army checkpoints every few miles along the roads.

For the past four months the school's director, Bandit Saleh, 45, has not left home without tucking his pistol into his trousers.

More and more teachers are arming themselves, with the help of the government, which has co-produced a gun catalogue offering discounted prices on weapons by manufacturers including Smith & Wesson, Colt and Beretta.

The education ministry plans to distribute bullet-proof vests to teachers, who as government employees are seen by insurgents as representatives of the central government in Bangkok.

So far 25 have been killed, the latest on Tuesday night, shot as he rode his motorcycle home.

The government has announced that it will buy seven American attack helicopters and more than 24,000 guns to fight the insurgency.

Saleh is not optimistic that the Chinese-made 9mm he carries will help. "At least if anything happens, then before I die I have a chance to fight back," he said.

Thawin Suwanlee, 47, who has been teaching mathematics for 25 years in the province, has applied for a 9mm Glock automatic through the teachers' federation. It will cost him about £500 (Dh3,220), payable in instalments.