Law-enforcement authorities from China, Laos, Myanmar and Thailand joined forces on Tuesday for the start of the 95th Mekong River joint patrol.

Two Chinese vessels departed from Jingha Port, Xishuangbanna Dai Autonomous Prefecture, in southwest China's Yunnan Province, while vessels of the other three countries departed from ports in Laos and Myanmar. The patrol will last four days and three nights.

Before the patrol, law-enforcement authorities of the four countries held a video conference to discuss the security situation of the river and reach agreement on jointly cracking down on illegal activities such as drug and gun-related crimes.

The Mekong River, known as the Lancang River in China, is a vital waterway for cross-border shipping.

China, Laos, Myanmar and Thailand have been carrying out joint patrols on the Mekong River for eight years.