BEIJING, December 1 (RIA Novosti) - A coal mine explosion in northern China has killed 18 people, including three rescuers, the Xinhua news agency reported on Monday.

The blast occurred on Sunday at the Changlong coal mine in the Heilongjiang province when some 25 miners were underground. Only 10 of them managed to escape, and the other 15 remained trapped in the mine, Xinhua said.

Three rescuers died in a cave-in on Monday. More than 100 people were involved in the rescue operation, the agency said.

The cause of the blast is being investigated. The coal mine has annual production capacity of 40,000 metric tons.

China's mining industry is considered one of the world's most dangerous, with accidents killing up to 7,000 workers annually. A major gas blast at Liaoning's Sunjiawan mine in February 2005 killed more than 200 miners, making it the worst mining tragedy in China for at least 15 years.