SALUTE: Residents attend a flag-raising ceremony on the Yongxing Island on July 23 (ZHAO YINGQUAN)

As China's youngest city to administer about 2 million square km of islands, coastal areas and territorial waters in the South China Sea, Sansha in Hainan Province was established on July 24, 2012, as an important base to safeguard China's sovereignty and serve marine resources development. It is the country's smallest prefecture-level city by both population and land area, but the largest by water area and the southernmost.

Sansha gets its name from three island groups under its jurisdiction—Xisha, Zhongsha and Nansha—and their surrounding waters in the South China Sea.

OFFICIAL RECOGNITION: Liang Feng, a resident on the Zhaoshu Island in Sansha City, shows off his new ID card on July 17 (ZHAO YINGQUAN)

According to the Sansha Government, at the end of 2012, the city had a permanent population of 833 and only 233 of them, mainly fishermen, registered their households in Sansha. However, areas under the jurisdiction of Sansha have 80 percent of China's undersea oil and gas resources, and 30 percent of China's imports and exports travel through waters administered by Sansha.

On March 9, the China Marine Surveillance (CMS) stationed a detachment in Sansha. Its deputy head, Yang Zhong, said that the team will carry out regular patrols and observations including the management of maritime space and protection of marine and island ecology.

"It means the CMS has enhanced its administrative management over Sansha's waters, and effectively covers the whole South China Sea," said Zhang Weijian, an official with the CMS South Sea fleet.