Members of the Armed Forces of the Philippines and their counterparts from the United States military join the opening of the 39th iteration of Balikatan at Camp Aguinaldo in Quezon City on April 22, 2024. Jonathan Cellona, ABS-CBN News

WEST PHILIPPINE SEA — China's People's Liberation Army (PLA) Navy on Sunday withdrew its surveillance vessel and replaced it with a warship to tail the flotilla of Philippine, American and French vessels conducting naval drills in the West Philippine Sea.

At 6 a.m., PLA Navy vessel 570 -- also known as Chinese frigate Huangshan -- was seen monitoring the Balikatan exercises naval convoy some 50 nautical miles west of Palawan.

"Wala naman silang challenges na inissue kanina since ang distance nila medyo malayo, nasa nine nautical miles," said Commander Marco Sandalo, commanding officer of the BRP Davao del Sur.

"Sa tingin ko hindi naman magiging concern yun. Presently we are conducting activities na safe and dire-diretso at successful naman yung different serials natin for the day," he said.

(They did not send radio challenges since their distance is quite far at 9 nautical miles. I think this should not be a cause of concern. Presently we are conducting activities safely and unimpeded, and our different serials for the day have been successful.)

The Jiangkai II class frigate, which is part of China's South Sea Fleet, also tailed seven Philippine and US vessels in January as the allied navies conducted the Maritime Cooperative Activity (MCA), another form of joint drills in the West Philippine Sea.

It remains unclear why the PLA replaced its surveillance vessel for hours with a warship armed with anti-submarine capabilities in monitoring this year's Balikatan exercises.

READ: Chinese navy ship shadows Balikatan convoy in West Philippine Sea

After nine hours, PLA Navy's surveillance vessel 793 took the place of the warship and resumed its shadowing tactics.

"Paminsan-minsan pasulpot-sulpot. Paminsan-minsan nandiyan sila tapos biglang mawawala so ang importante namo-monitor natin ang kanilang presence at naipapahatid natin 'yung kanilang movement sa higher headquarters," Sandalo said.

"Ang pinaka importante dito ay we are conducting yung mga activities natin beyond our territorial sea na safe and successful," he added.

(They will appear and then disappear. Sometimes they're there, then they're not. So what's important here is we are monitoring their presence and we are reporting their movement to higher headquarters.)

While some fishing vessels were also sailing over a dozen nautical miles away from the exercise area, Sandalo said there was no confirmation if these were part of China's maritime militia.

"Hindi namin masabi na Chinese maritime militia vessel kasi marami ring talagang mga fishing vessels within this area, that includes yung mga Filipino fishing vessels na nadaanan natin," he said.

"So ang masasabi lang natin ay there are plenty of fishermen within the area," he said.

(We can't say that they are Chinese maritime militia vessels because there are many other fishing vessels within this area, that includes Filipino fishing vessels which we passed by. So the only thing we can say is that there are plenty of fishermen within the area.)

Beijing has repeatedly slammed Manila for holding military drills in the West Philippine Sea — an area which falls within the Philippines' exclusive economic zone — as China continues to claim nearly the entire South China Sea despite a 2016 international arbitration ruling that their 9-dash line map had no legal basis.

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Despite China's continued presence, the BRP Davao del Sur, BRP Ramon Alcaraz and the USS Harper's Ferry proceeded with its naval drills, including a maritime search and rescue exercise.

"Itong maritime search and rescue is designed or is a technique in order for us to conduct yung rescue nung mga na-man overboard na passenger sa isang barko," Sandalo said.

"Kunyare may lumubog na barko ay kakailanganin ng mga pasaherong sibilyan ng tulong and at the same time puwede din sa aircraft kapagmay na-down na aircraft, yung mga pasahero nila ay kailangan natin ma-rescue," he said.

(This maritime search and rescue is designed or is a technique in order for us to rescue individuals who were thrown overboard a ship. For example, if a vessel sank and there are civilians who need help, and at the same time, this can also be used if there is a downed aircraft whose passengers need to be rescued.)

For the second time since the multilateral maritime drills started, French frigate FS Vendemiaire pulled out to return to Puerto Princesa as a personnel needed to undergo medical tests and treatment.

"Presently, hindi pa natin masabi kailan ang balik niya pero most likely she will be joining the next succeeding serials," Sandalo said.

(Presently, we cannot say when she will return but most likely she will be joining the next succeeding serials.)

Landing platform dock USS Somerset is expected to join the Balikatan exercises by the evening of April 28.

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