Why the Philippine Coast Guard is Worried About Chinese Research Vessels

The Philippine Coast Guard (PCG) on Tuesday expressed concern after it spotted a Chinese research vessel in Ilocos Norte amid tensions in the disputed South China Sea between Manila and Beijing.

In a statement, PCG spokesman Commodore Jay Tarriela said the Tan Suo 3 ship was illegally conducting marine scientific research within the Philippines’ 200 nautical mile exclusive economic zone (EEZ). A manned deep-sea submersible was also seen approaching the Chinese vessel, which was retrieved by its crew.

“The only thing that is worrisome is that it has the capability for deep sea mapping, which can be used for submarine deployment as well,” he said.

The coast guard official noted that the unauthorized research activity within Manila’s territory risks national security.

The Chinese Embassy in the Philippines did not immediately respond to a request for comment.

On Monday, the PCG reported spotting the Tan Suo 3 entering the Philippine exclusive economic zone around 92 nautical miles off Burgos in Ilocos Norte last May 1. The Philippines sent out the BRP Teresa Magbanua and an aircraft to monitor, challenge and escort the vessel out of Philippines’ maritime territory.

Tarriela raised the alarm that through the submersible named the Deep-Sea Warrior, deep-sea exploration would be possible with the capacity to dive to depths of 4,500 meters

The PCG also found a rigid hull inflatable boat with unidentified pieces of equipment possibly linked to marine research activities.

“So in the security part, I think that's the only concern for the marine scientific research, the illegal marine scientific research that they are conducting,” the coast guard spokesman said.

Last month, another Chinese research ship, the Zhong Shan Da Xue, was also spotted near the waters of Batanes, the northernmost province of the Philippines. The Philippine Navy last year also observed the Chinese research vessel Ke Xue San Hao with high-tech equipment for marine environment observation and which could have been causing environmental damage.

Philippine Navy spokesman Roy Trinidad has said that China’s reclamation in the South China Sea had reached about 3,000 hectares.

The Hague-based United Nations Permanent Court of Arbitration has voided China’s sweeping claims of over 80 percent of the South China Sea for having no legal basis.

“These actions of the Chinese research vessel serve as clear evidence that the People’s Republic of China is conducting illegal marine scientific research activities within the Philippines’ Exclusive Economic Zone, lacking the legal authority to undertake such activities in this area,” Tarriela said in an X post.

US and Philippines Reaffirm Vow To Keep The Peace

Meanwhile on May 5, US Chairman of the Joint Chiefs of Staff Dan Caine spoke on the phone with his Philippine counterpart, Armed Forces of the Philippines Chief of  Staff General Romeo Brawner, Jr. 

In a statement, Caine's office said both officials vowed to boost bilateral and multilateral engagements to keep the peace and to ensure peace and security in the region.  

"The US-Philippines' bilateral security partnership is key to managing emerging threats across the Indo-Pacific region," it said.

The US last month deployed its advanced anti-ship missile system in the northern part of the Philippines for combat exercises as part of the yearly Balikatan war games, which has drawn China's ire for jeopardizing regional peace. The Philippines and the US are bound to defend each other through their Mutual Defense Treaty, in the event of armed conflicts and attacks.

However on Monday, US and Philippine forces canceled a live-fire drill after a World War-II era ship sank due to rough sea conditions while being towed from the planned anti-ship missile fire site.

More than 14,000 troops from both nations are participating in the Balikatan wargames, held in potential regional flashpoints in the disputed waters near Taiwan. These will run from April 21 to May 9.

"The US remains committed to the ironclad alliance with the Philippines, rooted in shared interest and democratic values," according to Caine's office.