Rescuers are searching for six sailors missing in the sea off China's northeast coast Tuesday, two days after a fishing boat collided with a cargo vessel.

Nine people fell into water when the collision occurred at midnight Sunday in the sea off Lushun, Liaoning Province, the Liaoning Maritime Search and Rescue Center said in a statement sent to Xinhua Tuesday. Three of the nine have already been saved.

A helicopter and two rescue boats are searching for the missing sailors.

Rescuers found the fishing boat Tuesday morning.

Maritime authorities have launched an investigation into the accident.