Washington — U.S. intelligence agencies are closely monitoring activity at a disputed shoal in the South China Sea amid growing concerns that China may be laying groundwork for more permanent presence, potentially inflaming tensions with the Philippines and testing Washington’s commitment to its treaty ally.
Recent Chinese maritime operations near Scarborough Shoal have sparked scrutiny from U.S. officials familiar with intelligence. The Chinese government installed what Beijing calls a “scientific structure” in the reef, which has angered the Philippines due to its disputed status.
U.S. engagement over the structure was met with mixed responses from China’s military wing, the People’s Liberation Army (PLA). While PLA officials claimed the structure is not military, they did not fully disavow that some elements could be used by them.
The Office of the Director of National Intelligence has yet to comment on the situation. The Scarborough Shoal, known as Bajo de Masinloc in the Philippines and Huangyan Dao in China, lies within Manila’s exclusive economic zone but Beijing maintains near-constant presence around it following a tense standoff in 2012.
Some U.S. officials worry that recent activity could represent another step in China’s long-term effort to consolidate control over disputed features across the South China Sea, a view shared by Philippine officials.
Philippine authorities disclosed the floating structure inside Scarborough Shoal earlier this week. The National Task Force for the West Philippine Sea stated aerial surveillance identified a 6-by-6-meter platform equipped with an antenna and personnel atop it. Monitoring by the Philippine Coast Guard confirmed the platform was operating within the shoal.
The Department of Foreign Affairs has taken diplomatic action against China in connection with the structure, assessing its nature, purpose, and implications. However, China maintains that the platform is located in its controlled area, not the Philippines’.
China rejects Philippine objections, asserting sovereignty over Huangyan Dao and adjacent waters. Liu Pengyu, an embassy spokesperson for China, stated that it is within China’s sovereign rights to carry out activities at the site.
The development has drawn attention from U.S. intelligence analysts and military planners due to China’s history of gradually establishing control over disputed maritime features before expanding its presence. Over the past decade, Beijing transformed several reefs in the Spratly Islands into fortified artificial islands equipped with airfields, ports, radar systems, and missile sites.
“Over the past 20 years we’ve witnessed the largest military buildup since World War II by the PRC,” said retired Navy Adm. John Aquilino in 2022. “They have advanced all their capabilities and that buildup of weaponization is destabilizing to the region.”
Concerns about Chinese activity in the area have been a recurring feature of U.S. military planning. Last year, plans were drawn up for a show of force against recent Chinese aggression near Scarborough Shoal intended to signal Washington’s intent to push back against Beijing’s expanding presence and defend Philippine sovereignty and fishing rights.
Last year, Beijing announced it would create a national nature reserve in the area, drawing condemnation from U.S. Secretary of State Marco Rubio and viewed by Manila as another step toward solidifying Chinese control.