The Philippine Coast Guard (PCG) conducted a Maritime Domain Awareness (MDA) flight on 17 May 2026 to address and drive away unauthorized marine scientific research (MSR) activities being conducted by a Chinese research vessel in the vicinity of Cay-2 and Cay-3, which falls inside the territorial sea of Pag-asa Island.

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, …

The location referred to by the Chinese Embassy is Pagasa Island and the Pagasa Cays, which form an integral part of the Kalayaan Island Group of the Philippines. These features have never been part of China. The recent activity in this area was undertaken by Philippine civil society and was not the result of any deployment or operation ordered by the Philippine government.

This area lies several hundred nautical miles from the Chinese mainland. It therefore cannot infringe upon any legitimate Chinese territorial sovereignty, as none exists here under international law. China cannot …