PCG: Illegal marine research by China vessel seen at Pag-asa Cays

The Philippine Coast Guard (PCG) has monitored unauthorized marine scientific research (MSR) activities by a Chinese research vessel in the vicinity of Cay-2 and Cay-3 near the Pag-asa Island in the West Philippine Sea over the weekend.

On May 16, the PCG monitored the Chinese research vessel Xiang Yang Hong 33, which is equipped to support submersibles, map the seafloor, gather deep-sea data, and perform extensive marine ecological studies.

“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,” the PCG said in a statement.

The Xiang Yang Hong 33 left Guangzhou, China on April 15, before crossing into the West Philippine Sea three days later on April 18, the agency added.

Since its entry into the Philippines’ exclusive economic zone (EEZ), the Chinese research vessel “has been systematically conducting illegal MSR activities across multiple features in Philippine waters.”

History trail of Xiang Yang Hong 33 from April 15, 2026 to May 17, 2026 via AIS. )Photo from Philippine Coast Guard)

In response, the PCG’s Islander 4177 aircraft conducted a maritime domain awareness (MDA) flight over the Kalayaan Island Group on Sunday.

The PCG also conducted multiple radio challenges to the Chinese vessels.

“The flight monitored the unauthorized operations near Sandy Cay 2 and confirmed the presence of the Chinese research vessel and its support vessels engaged in MSR without the consent of the Philippine government. The MDA flight also documented twenty (20) Chinese Maritime Militia Vessels (CMMVs) scattered in the surrounding waters of Sandy Cay 3 and 4,” the PCG said.

It added that the MSRs breached the country’s sovereignty and the United Nations Convention on the Law of the Sea (UNCLOS).

The PCG said there was no consent granted to China to conduct such activities, as international law mandates that any foreign state wishing to conduct MSR activities within another nation’s territorial sea must secure prior permission from the coastal state.

“The PCG remains steadfast in defending our maritime zones. We will not allow any unauthorized foreign research or incursions into our territorial sea in Pag-asa Island in accordance with the directive of President Ferdinand Marcos Jr.,” said PCG Commandant Admiral Ronnie Gil Gavan.

Pag-asa Island is located 277 miles away from mainland Palawan and is part of the Kalayaan Island Group within the disputed West Philippine Sea.

It covers an area of 32.7 hectares and is the largest among the Kalayaan Islands. — JMA, GMA News