What Happened Chinese and Vietnamese coast guard vessels have reportedly been engaged in a weeklong confrontation around Vanguard Bank in the southern region of the South China Sea. The standoff was allegedly sparked when the Chinese survey ship Haiyang Dizhi 8 entered the area on July 3 to carry out a mapping mission. The ship was escorted by several Chinese coast guard vessels and maritime militia ships, as well as dozens of merchant marine vessels. Some of these merchant vessels are believed to belong to some of its state-owned energy giants, including the China National Petroleum Corp. (CNPC) and the China National Offshore Oil Corp. (CNOOC). Meanwhile, Chinese coast guard vessels were recently spotted near Vietnam's Block 06.1 off the Vanguard Bank, which is where Japan's Hakuryu 5 oil rig had started drilling operations on May 12 under a contract with the Rosneft Vietnam B.V.