A cargo ship capsized in waters off the western coast of Hainan Island late Saturday night, leaving two crew members missing, local authorities said.

The incident occurred at around 10 pm on Saturday, when improperly secured cargo tilted and overturned the vessel, causing six crew members to fall into the sea, according to reports received by the Danzhou coast guard bureau in Hainan province.

As of 5 pm on Sunday, four of the crew members had been rescued, while two others are still missing, the bureau said.

Rescue vessels from the coast guard and local maritime authorities are conducting joint search and rescue operations in the area.