On 16 May 2026, PCG monitored the China-flagged research vessel Xiang Yang Hong 33, an advanced oceanographic survey vessel capable of supporting submersible craft and conducting comprehensive marine ecological surveys, bathymetric mapping, and deep-sea data collection. The vessel was escorted by Chinese Coast Guard vessels CCG 5101 and CCG 5309, which deployed rigid-hulled inflatable boats (RHIBs) and rubber boats. Chinese personnel were observed landing and conducting illegal activities on Cay-2 before proceeding to Cay-3.