SHANGHAI: Rescue teams on Wednesday drilled new holes down a gold mine in China's Shandong province, searching for more survivors after an explosion 10 days ago and preparing an escape passage for a group known to still be alive, state media reported.

A total of 22 workers were trapped underground in the Hushan gold mine on the outskirts of Yantai, on China's eastern coast, following the Jan. 10. blast. Rescuers have managed to deliver supplies to 11 workers, one of whom is in a coma after sustaining a head injury during the explosion.

Another eight of the 11 are in good health, while two are unwell, Shandong's official Qilu Daily newspaper said, citing the rescue headquarters. One more worker who survived is in another section of the mine and believed to be injured, while the whereabouts of the remaining 10 are unclear, it added.

China has deployed 16 professional rescue teams and dozens of medical personnel to try to save the miners.

Song Xicheng, the medical rescue team leader, told reporters that more than 80 medical personnel were on standby, including nutritionists, neurosurgeons, trauma specialists and psychologists.

The operation involves drilling 10 channels, with one 711 millimetre-(2.33-foot)-wide hole - intended to serve as an escape route - wide enough to lift out the miners, the People's Daily said. Rescuers could not say when this hole would be finished but admitted they were in a race against time.

An air ventilation shaft that rescuers also want to use to pull the miners to safety has been cleared to a depth of 350 metres (1,148 feet), the report said. The miners were working at a depth of more than 600 metres at the time of the explosion.

A channel previously used to send down supplies has been replaced because water inside was posing a threat to those underground, while another hole is being drilled to search for more signs of life, Beijing Evening News reported.