BEIJING - Four provincial-level administrative regions in South China have carried out their first joint patrol in the South China Sea with one of the country's largest marine patrol ships, the Beijing Daily reported Thursday.

The joint patrol, launched by the maritime safety administrations of Guangdong, Hainan and Fujian provinces and Guangxi autonomous region on Wednesday, was aimed at ensuring maritime traffic security and safeguarding national maritime sovereignty, Shen Chunsheng, deputy head of the Guangxi Regional Maritime Safety Administration, was quoted as saying.

The joint patrol team, led by the Haixun 31 patrol ship, is expected to travel 500 nautical miles through a number of harbors and key passages in five days.

It will check the navigation, berth and operation of vessels in the South China Sea waters, verify the navigation environment in China-Vietnam maritime border areas and curb some vessels' illegal practices that result in ocean pollution, Shen said in the report.

A joint patrol will cement maritime patrol and law enforcement cooperation among the four provincial regions, serve as a deterrent force and guarantee long-lasting traffic security in the South China Sea, said Shen.