Chamnong Chupatpong, the director of Bado elementary school in Thailand, and teacher Manoe Sonkawe were in a pickup truck when four militants on motorbikes drove up and shot them at close range in late December.
Their bodies were soaked with petrol and set alight on a road 100 metres from the school, according to The Nation newspaper. Spikes had been placed across the road to slow down police chasing after the attackers.
Human Rights Watch said the two teachers were victims of a wave of separatist violence that erupted in Thailand's three most southerly provinces in January 2004 and has so far claimed about 2,000 lives.
'Schools should be safe zones,' said Sheldon Shaeffer, the director of Unesco's regional bureau for education in Bangkok.
'But they are highly visible targets and attacking them does more to grab the attention of the country or the world than attacking government offices.'
In addition to the 73 Muslim and Buddhist teachers or education workers murdered since the start of the insurgency, 16 students have been killed and 130 schools burned down.