A man set fire to a cylinder of liquefied petroleum gas in a house in the village of Jinjujiuwei in Dongguan, Guangdong province, during a police raid on a tip that people inside were trading and using drugs. Three of the five people inside were killed.
Two suspected drug users tried to escape but were captured by the police, Southern Metropolis Daily reported.
The police found drug paraphernalia and apparent drugs in the house. The five, including the deceased, all tested positive for methamphetamine, or ice.
Four of the five had been punished for taking and dealing in drugs several times since 2005, with one of the dead still to be identified.