Law enforcement authorities from China, Laos, Myanmar and Thailand joined forces on Tuesday to conduct the 111th joint Mekong River patrol.

Two Chinese vessels departed for the patrol at 9 a.m. Tuesday from Jingha Port in the Xishuangbanna Dai Autonomous Prefecture of southwest China's Yunnan Province, the Yunnan public security department said.

Prior to the operation, law enforcement authorities held video conferences to jointly analyze public security situation in the river basin amid the COVID-19 pandemic.

During the patrol, the four countries conducted joint law enforcement activities in key sections of the river and made efforts to ensure the river basin's security and stability.

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 of the river since December 2011.

(Cover: The enforcement personnel participating in the 88th Mekong River joint patrol are seen at Guanlei Port in southwest China's Yunnan Province, November 19, 2019. /Xinhua)