A group of photos taken from Nov 19 to Nov 22 showed Chinese border forces patrolling the Mekong River. The four-day joint patrol, from Nov 16 to 20, was the 16th round since it was launched by China, Thailand, Myanmar and Laos in December 2011 to enhance safety of marine traffic on the river which borders the four countries. The 17th joint patrol is to start on Dec 19. Hijackers killed 13 Chinese sailors on two cargo ships in a Thai section of the waterway on Oct 5, 2011. [Photo by Hu Yongqi/chinadaily.com.cn]