BEIJING, Nov. 10 (Xinhua) -- The number of colliery gas accidents in China fell by 11.4 percent in the first three quarters of this year, according to the National Development and Reform Commission (NDRC), the country's top economic planning agency.

The 210 gas accidents in the Jan.-Sept. period claimed 752 lives, down 14.1 percent from the same period a year ago.

The most two serious accidents, both of which took place in north China's coal-rich province of Shanxi, killed a total of 61 people.

Although most provinces reached their targets of reducing gas accidents, the overall situation remained grave, said a statement posted on the NDRC's website.

"The fourth quarter, especially November, has always been prone to colliery gas accidents" and local governments must tighten supervision on coal mines and help them remove the hidden danger, it added.

China, the world's largest coal producer, has been striving to improve work safety in its mines. But accidents are still frequent as enforcement is lax and mine owners push production beyond safety limits to seek high profits.

The country has launched a campaign to close small coal mines, which account for one third of its total coal output but two thirds of the deaths from colliery accidents.