Nearly 1,500 police officers and professional rescue workers have reportedly joined the effort to save the 21 remaining trapped miners in northwest China's Xinjiang region.

Eight out of the 29 miners trapped inside the flooded coal mine were rescued Sunday.

Local emergency department officials said the Fengyuan coal mine in Hutubi County was flooded after a power outage on Saturday night. The 29 coal miners were reportedly working inside the mine located in Xinjiang when the flooding started.

They were reportedly conducting upgrading works at the mine when the disaster struck.

Officials said at least 12 of the 21 remaining trapped miners have been located and rescuers are still attempting to locate the other nine lost workers.

Dozens of residents, including the family members of the trapped miners, have since gathered at the entrance to the flooded call mine to cheer on the rescue workers. Some have brought banners saying that home is waiting for the trapped miners.

Chinese state-controlled broadcaster CCTV said the 12 miners that were located were found inside one platform. The other eight are believed to be trapped on a second platform, while another one may be trapped in an escape route where the water had entered.

"The working platform with 12 people is 1,200 meters (3,900 feet) from ground level and the underground terrain is complex, making rescue difficult," CCTV said

Chinese mines are considered to be among the deadliest in the world with dozens of workers dying each year from gas leaks and accidental explosions. In January, 10 gold miners in China's coastal Shandong province lost their lives following an accidental explosion.

In December last year, 23 miners were killed after they were trapped inside a mine in the southwestern city of Chongqing. In September, 16 miners lost their lives after being trapped inside a coal mine in the same area.

In 2020, a total of 73 miners had lost their lives in nine separate mining accidents throughout China.