China says two cargo ships have collided off the coast of the eastern city of Qingdao, causing one of the freighters to sink.

China's state-run news agency, Xinhua, reports that nine of the crew of the sunk vessel were rescued Friday evening while another 10 are still missing. It says all of those who were on that vessel are believed to be North Korean.

Officials say three of those rescued have been sent to the hospital for treatment.

Xinhua did not give the nationality of the crew members on the other ship involved in the collision or say who owned the two vessels.

It says 13 ships are now in the area of the accident to help with the search and rescue operation.