Philippines - May 05, 2025 Ilocos Norte, Philippines – The Philippine Coast Guard (PCG) confronted a Chinese Research Vessel (CRV) in a high seas standoff on May 5, 2025, off the coast of Ilocos Norte. The CRV Tan Suo 3 was detected on May 1, 2025, approximately 92 nautical miles from Burgos, operating inside the Philippine Exclusive Economic Zone (EEZ). On May 5th, the PCG deployed the BRP Teresa Magbanua and launched a PCG aircraft from Laoag to support the maritime law enforcement operation. Both assets conducted maritime domain awareness flights and issued radio challenges. The PCG confirmed that their operations were in accordance with the Philippine Maritime Zones Act, the United Nations Convention on the Law of the Sea, and the 2016 Arbitral Award. The crew of the CRV was informed that they were violating the Philippines’ sovereign rights. Their irregular movements were considered consistent with illegal marine scientific research. They were ordered to stop their activities, explain their intentions, and continue transiting without delay. During the operation, a manned deep-sea submersible, SHENHAI YONGSHI (Deep-Sea Warrior), approached the CRV and was retrieved by its crew. The submersible is capable of diving to depths of 4,500 meters and is used for scientific exploration. A Rigid Hull Inflatable Boat was also deployed to collect a yellow unidentified piece of equipment, likely linked to marine research. The PCG stated these actions showed that the People’s Republic of China was conducting unauthorized research in Philippine waters. The Chinese vessel did not respond to radio challenges, focusing instead on recovering the submersible. PCG Commandant Admiral Ronnie Gil Gavan reaffirmed the agency’s commitment to defending Philippine maritime sovereignty in the West Philippine Sea.