Beijing  - The death toll rose to 42 from a gas explosion at a coal mine in the central Chinese province of Henan as 37 people remained missing underground, the government said Wednesday.

The blast ripped through the Xinhua Number 4 mine in Pingdinghsan city as 93 miners were working there Tuesday, the State Administration of Work Safety said.

Fourteen workers escaped after the explosion, the administration said.

It said the privately run mine was in the process of a technological upgrade and had resumed operations without permission from local authorities.

The official Xinhua news agency on Wednesday said two local officials in Pingdingshan were sacked after the accident.

A preliminary investigation by safety officials at the site suggested that "illegal production" was to blame for the accident, the agency reported from Pingsdingshan.

Local authorities reportedly froze the mine's bank account and the mine owners were kept under police surveillance, it said.

The agency said the mine was township-owned, rather than privately owned, and licensed to produce 150,000 tons of coal annually.

China reports thousands of deaths at coal mines each year, but the exact total remained unclear because many mine owners fail to report deaths or injuries to try to prevent the suspension of work by authorities.

Henan province alone, one of China's top 10 coal-mining provinces, reported 1,699 deaths in the first eight months of this year, a decrease of 22 per cent from the same period of 2008, Xinhua said.

The accidents are often triggered by outdated equipment and poor safety measures with many occurring at illegal mines.

After Tuesday's explosion, the provincial government ordered immediate safety inspections of all coal mines in Henan while the Pingdingshan city government suspended production at all 157 coal mines in the city, the agency said. (dpa)