MANILA –– The Philippines has asked China to explain its coast guard's seizure of rocket debris from Filipino soldiers in disputed waters, the Department of Foreign Affairs said on Thursday.

A senior Filipino navy official on Monday accused the Chinese coastguard of "forcefully" seizing parts of a rocket fairing that landed in the waters of the Spratly Islands in the hotly contested South China Sea. But Beijing insisted the handover took place after "friendly consultation".

President Ferdinand Marcos Jr. said Tuesday Manila would send a diplomatic note to Beijing asking "why is it that their account is so different and it's much more benign".

• Chinese embassy denies 'forceful seizure' of rocket part near Pag-asa Island

“Yes, a Note Verbale has been sent following the instruction of the President," Department of Foreign Affairs (DFA) spokesperson Teresita Daza said in a text message.

“As explained by the Secretary the note seeks clarification from the Chinese side over the incident involving the Philippine Navy and the Chinese Coast Guard in the vicinity of the waters of the Pag-asa Cays on 20 November 2022," the agency added.

The South China Sea is a longstanding source of tensions between the two nations.

Beijing claims sovereignty over almost the entire sea and has ignored an international court ruling that its claims have no legal basis. The Philippines, Vietnam, Malaysia and Brunei have overlapping claims to parts of it.

Marcos earlier said he had "complete trust" in the navy's account of the rocket seizure.

"If this is what they say happened, I can only believe that that is what happened," he said.

Marcos's remarks came as US Vice President Kamala Harris wrapped up a visit to Palawan near the disputed sea in a show of support for the longtime US ally.

Harris said the United States "stands with the Philippines in the face of intimidation and coercion in the South China Sea."

• US VP Harris reaffirms ties with PH in meeting with Marcos

Marcos has insisted he will not let China trample on the Philippines' maritime rights -- in contrast to his predecessor Rodrigo Duterte who was reluctant to criticize the superpower.

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In Sunday's incident, a Chinese coastguard vessel "blocked" a Filipino rubber boat towing an "unidentified floating object", Vice Admiral Alberto Carlos said Monday.

The Chinese coastguard vessel then deployed an inflatable boat team which "forcefully retrieved said floating object by cutting the towing line attached to the (Filipino) rubber boat", he said.

The object was then taken to the Chinese coastguard vessel as the Filipino troops returned to their station, Carlos said.

Philippine National Security Adviser Clarita Carlos said Tuesday the Filipino sailors "heard shots" apparently fired from an unknown location as they towed the object to the Philippine-garrisoned Pag-asa (Thitu) island.

• Pag-asa residents hear 'thunder-like' sounds after rocket debris spotted

"With the way that the region, our region the Asia Pacific, is heating up, there might be a small mistake, a misunderstanding that could blow up," Marcos warned.

He said his planned visit to China in January could be an opportunity to find a way to avoid further incidents.

"We want to have a mechanism, we have to find a way to prevent this from happening again," he said.

• Xi wants ‘to write new chapter’ in PH-China relations

— With reports from Willard Cheng, ABS-CBN News; Agence France-Presse

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