Nine coal miners were killed and 16 injured in a blast at a colliery in northern China on Monday, state media said, the latest accident to hit the notoriously dangerous industry in the country.

Four people were killed on the spot when the explosion rocked the mine in Bayannur city, in Inner Mongolia, and five more bodies were found hours later by rescuers, the Xinhua news agency said.

The injured, four of whom were badly hurt, were being treated in hospital, the report said, citing a spokesman of the local government. The cause was being investigated, he said, but the mine was licensed.

Nearly 2,000 miners were killed last year, according to official figures.

China's mines are known for being among the world's most deadly due to lax regulation, corruption and inefficiency, and accidents are common as safety is often neglected by bosses seeking quick profits.

Rapid economic growth has caused China's demand for energy, including coal, to surge. The world's second-biggest economy is the top global consumer of coal.

Inner Mongolia holds China's largest coal reserves.