Twenty-four miners were confirmed dead and eight were missing after an explosion tore through a coal mine in northwest China's Shaanxi province, the official Xinhua News Agency reported on Sunday.

Ambulances and police cars wait at the Dayaobao coal mine as rescue operation goes on April 30, 2006. [Xinhua]

The blast shook the Wayaobao Coal Mine in Yan'an at 4:20 p.m. Saturday after a gas build-up in the mine ignited, Xinhua said.

Only seven miners managed to escape to the ground. Some 39 miners were working beneath the shaft when the tragedy occurred.

Unlike many smaller mines across China, this one had all the necessary production and safety permits, the report said.

More than 3,300 coal mine blasts, floods and other accidents claimed nearly 6,000 lives across the country last year, as mine owners -- motivated by soaring profits -- pushed production past safe limits to fuel the booming economy.

The head of the national coal mine safety watchdog said in early April that China would shut down all coal mines with an annual output under 30,000 tons by the end of 2007. The Wayaobao mine produced 31,000 tons in 2005, Xinhua reported.

But safety officials have acknowledged that the crackdown on unsafe mines has run into considerable resistance from owners and from local officials who often have a lucrative stake in them.