An explosion in a central China colliery on Monday left 46 miners trapped, state media reported, in the latest accident to hit the country's notoriously dangerous mining sector.
The blast happened near Pingdingshan city in the central province of Henan, the official Xinhua news agency reported, citing the State Administration of Work Safety.
State television said that a store of gunpowder kept underground at the Xingdong No. 2 Mine had detonated at about 1:40 a.m. (1740 GMT) with 72 miners working at the time.
Following the accident, 26 miners were brought to safety, according to Xinhua, which added that a search and rescue operation had been launched to find the remaining 46 missing miners, state television said.
China's vast coal mining industry is notoriously accident-prone because of lax regulation, corruption and inefficiency as mines rush to meet soaring demand. China relies on coal-generated power for about 70 of its electricity needs.
A total of 2,631 miners were killed in China last year, according to official figures, but independent labour groups say the actual figure could be much higher as many accidents are covered up to avoid costly mine shutdowns.
In March, a flood at the huge, unfinished Wangjialing mine in the northern province of Shanxi left 153 workers trapped underground. A total of 115 were recovered alive, in what was seen as a rare successful rescue for the industry.
Zhao Tiechui, head of the State Administration of Coal Mine Safety, said in February that China would need at least 10 years to "fundamentally improve" safety and reduce the frequency of such disasters.
"Awareness of safety and the rule of law is still low in some coal-rich areas and some coal enterprises," he said.
As part of its efforts to increase safety standards, the central government has levied heavy fines and implemented region-wide mining shut-downs following serious accidents.
But such actions have resulted in the under-reporting of accidents as mine bosses seek to limit economic losses, labour rights groups maintain.
The March disaster in Shanxi province set off a new round of official pledges to make the industry safer, but since then several other accidents have been reported, leaving dozens of miners dead.
The issue of mining safety is sensitive in China, as the workers that toil in mines are largely poor migrants whose interests the ruling Communist Party has vowed to protect.
Following Monday's accident, Zhao and Luo Lin, who is head of the state work safety bureau, travelled to the site in Henan to personally oversee rescue efforts, state media reports said.
