The 20-year-old monk was at a pagoda on top of a mountain when he doused himself with five litres of petrol on Saturday and set fire to himself, Battambang province deputy police chief So Sam An said.

"The monk completely believed in religion – he sat cross-legged and poured gas over himself and burned to death in order to sacrifice his body to Buddha," So Sam An said to AFP.

Other monks and nuns at the pagoda told police that the monk, Yin Keo, who had been in the monastery for three months, had repeatedly said he would die in a religious sacrifice.