MANILA - The Philippines protested what it regards as fresh "provocative acts" by Chinese vessels in the South China Sea, the Department of Foreign Affairs said Wednesday.

In a tweet, the ministry said Chinese government vessels made "unlawful issuance of over 200 radio challenges, sounding of sirens, and blowing of horns" against Philippine authorities "conducting legitimate, customary, and routine patrols over and around" its "territory and maritime zones."

"These provocative acts threaten the peace, good order, and security of the South China Sea and run contrary to China's obligations under international law," the DFA said.

The agency did not specify when the incidents happened.

@DFAPHL protested the unlawful issuance of over 200 radio challenges, sounding of sirens, and blowing of horns by Chinese government vessels against Philippine authorities conducting legitimate, customary, and routine patrols over and around the Philippines' territory and (1/2)

— DFA Philippines (@DFAPHL) October 20, 2021

Earlier this year, hundreds of Beijing's ships were also spotted around the West Philippine Sea, the country's EEZ in the vast, resource-rich South China Sea.

Philippines authorities had described their presence as an incursion.

The Philippine Coast Guard (PCG) continues to conduct patrols in the West Philippine Sea.

Beijing maintains a constant presence of coast guard and fishing boats in the international waterway to assert its claim of sovereignty, including hundreds in the Spratly islands, where Brunei, Taiwan, Vietnam and Malaysia also have claims.

This is despite the Arbitral Tribunal in 2016 concluding that there is no legal basis for China to claim historic rights to resources within the sea areas falling within its so-called "nine-dash line.”

China has refused to recognize the Award, calling it “illegal, null and void.”

President Rodrigo Duterte has refused to press China to follow the court's ruling, as he pursued investments and loans from the economic superpower.

In May, Duterte called the arbitral award a scrap of "paper" that belongs to the wastebasket. But that same month, he said he would not withdraw Philippine ships from the waterway.

Analysts and several countries earlier warned China of its incursions in the West Philippine Sea, as it could threaten regional stability.

• China incursion in Julian Felipe Reef may be prelude to occupation: Carpio

— With reports from Willard Cheng, ABS-CBN News

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