Naval officers on their watch inside the bridge of the BRP Davao Del Sur as they sail the West Philippine Sea on May 18, 2023. Jonathan Cellona, ABS-CBN News/File

MANILA — The Philippine Coast Guard (PCG) on Monday said it has deployed some of its assets to "monitor, challenge, and escort" out a Chinese research vessel detected off the coast of Burgos, Ilocos Norte last week.

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The PCG said it deployed BRP Teresa Magbanua and an aircraft, both of which engaged in radio challenges against Chinese Research Vessel (CRV) Tan Suo 3.

"They were instructed to cease their unlawful activities, clarify their intentions, and ensure continuous transit within the EEZ in compliance with both international and Philippine laws," the PCG said.

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RESEARCH EQUIPMENT SPOTTED

During the operation, the PCG said its personnel spotted a "manned deep-sea submersible vessel fast approaching the Chinese Research Vessel, which was later retrieved by its crew."

The PCG identified the submersible as the "Shenhai Yongshi or Deep-Sea Warrior."

"[It was] engineered for deep-sea exploration and scientific research, with the capability to dive to depths of 4,500 meters," the PCG said.

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The PCG also reported that a Rigid Hull Inflatable Boat (RHIB) was deployed to recover a "yellow-colored unidentified piece of equipment, which may also be associated with marine scientific research activities."

"These actions of the CRV serves as clear evidence that the People's Republic of China are conducting illegal marine scientific research activities within the Philippines' Exclusive Economic Zone, lacking the legal authority to undertake such activities in this area," the PCG said.

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The PCG said its operation "effectively prevented the CRV from continuing its unlawful activities." However, it did not say whether the Chinese research ship has left the Philippine waters.

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