BEIJING – A coal mine blast in northern China killed 15 miners and three rescuers died in a cave-in Monday morning.

BEIJING – A coal mine blast in northern China killed 15 miners and three rescuers died in a cave-in Monday morning.

China's coal mines are the world's deadliest. Coal is hugely important in China, feeding two-thirds of the economy's energy demand.

Fifteen miners were confirmed dead after the gas explosion Sunday afternoon in the Changlong Coal Mine in Heilongjiang province, the state-run Xinhua News Agency said. Twenty-five people were in the mine but 10 escaped.

The cause of the explosion in Qitaihe city is still under investigation, Xinhua said.

The report said three of the more than 100 rescuers at the site were killed in Monday's cave-in.

Heilongjiang and company officials could not be reached immediately Monday.

Last year, 3,786 miners were killed in China's coal mines, with 80 percent of the deaths at small operations like the privately owned Changlong mine, which Xinhua said produces 40,000 tons a year.

Under a government safety campaign, new mines that plan to produce less than 300,000 tons a year will not be given approval to open.