BEIJING (AP) — Rescuers on Friday pulled out nine of 25 workers trapped in a flooded coal mine, state media reported.

China Central Television showed footage of workers being carried out from the mine in northeastern Heilongjiang province. Sixteen miners remained trapped.

A total of 33 workers had been lifted to the ground after the flooding occurred Thursday afternoon at the privately owned Anzhishun Coal Mine in Jixi City, the official Xinhua News Agency reported earlier.

Xinhua said rescuers had been installing pumps to drain the shaft, and that the mine’s owner had been placed in police custody.

It gave no details on what caused the flood.

China has some of the world’s deadliest mines, but they are getting safer with stricter work safety enforcement.

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