Container line APL has said a fire has broken out in the cargo holds of a boxship travelling from Shekou to Singapore.

Emergency response procedures were activated for the 9,200-teu APL Vancouver (built 2013) off Vietnam in the early hours of Thursday.

"The operator is in continuous contact with the vessel’s master and local authorities to coordinate all necessary actions to ensure the fire is safely and promptly extinguished," APL said.

"The situation is being closely monitored and relevant parties have been informed."

The Laodong website said coast guard personnel were sent to the scene, four miles from the coast.

They were coordinating with the 24 crew, who had not been injured.