KUNMING, Aug. 18 (Xinhua) -- Law-enforcement authorities from China, Laos, Myanmar, and Thailand joined forces on Tuesday for the start of the 96th Mekong River joint patrol.

Chinese vessels departed from the Guanlei Port 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 on the river and reached an agreement on jointly cracking down on illegal activities such as stowaways, telecom fraud, and drug 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.