Chinese authorities have dispatched rescue workers to a gold mine in the country’s northeast after 22 workers were trapped underground following an explosion.

The accident happened in Xicheng Township, located in eastern Shandong province. Rescue workers have so far been unable to contact the trapped miners because the blast damaged the communication signal system.

The mine was owned by Shandong Wucailong Investment Co Ltd. That company is named by Zhaojin Mining, China’s fourth-biggest gold miner, as a related party/“subsidiary of an associate” in its 2019 annual report.