Seoul, Oct 28 : A tense maritime standoff unfolded in the Yellow Sea last month when Chinese Coast Guard vessels blocked a South Korean research ship operating in an overlapping sea zone, according to a report released by the Center for Strategic and International Studies (CSIS) on Tuesday.
The Washington-based think tank, in its report titled “Korea-China Standoff in the Provisional Measure Zone (PMZ),” revealed that the incident occurred on September 24, when the South Korean research vessel Onnuri entered the Provisional Maritime Zone (PMZ) — an area jointly claimed by both nations — to inspect Chinese-built steel structures.
Citing data from Starboard Maritime Intelligence, CSIS reported that approximately six hours after the Onnuri began its inspection, a Chinese Coast Guard ship approached, followed by two additional vessels from Qingdao. In response, a South Korean Coast Guard ship was dispatched to the site for protection.
The following day, both South Korean vessels neared two Chinese aquaculture facilities, Shenlan No. 1 and Shenlan No. 2, when Chinese Coast Guard ships surrounded the Onnuri, preventing it from conducting inspections. The standoff persisted for about 15 hours, with Chinese vessels shadowing the Koreans until they exited the PMZ.
This marked the second such confrontation in seven months, the previous one having occurred in February. The CSIS noted that the incident reflects Beijing’s growing assertiveness and surveillance efforts in disputed maritime zones.
The think tank added that China’s actions violate the United Nations Convention on the Law of the Sea (UNCLOS), which guarantees freedom of navigation within Exclusive Economic Zones (EEZs).
South Korean Foreign Minister Cho Hyun confirmed that the U.S. is closely monitoring the matter, as the disputed area lies near the U.S. military base in Pyeongtaek, and said Seoul will consider cooperating with Washington based on future developments.











