Calling it unacceptable, the CatSU condemned the intrusion and urged the vessel to comply with international maritime laws.

As the conscience of their society, they unite to protect their seas and lands from encroachment and unlawful activities, the CatSU said.

In a statement of solidarity, Bicol University (BU) said it supports CatSU's protest against the Chinese vessel loitering in Catanduanes waters.

BU said the vessel’s presence in the area posed a potential threat to ongoing or future research engagements.

BU “will never tolerate any unauthorized engagements,” especially those that may infringe on heritage and sovereignty, particularly in identified territorial waters, said the premier academic institution in Bicol.

As responsible stewards, it must speak up and express care, concern, and accountability for protecting the nation’s natural resources, BU said.

On the other hand, the Catanduanes State University Student Council (CSUSC) and CatSU Office of the Student Regent supported those concerned about Chinese vessels in Philippine waters, with the one recently spotted off Catanduanes.

Student Regent Francine Mae Tayo, also the CSUSC chair, stated that they “refuse to stand by and watch our marine resources be threatened by foreign interests.”

Saturday’s intrusion of a Chinese vessel into the Philippine Sea is part of a pattern of frequent incursions by Chinese ships.

The Philippine Sea is opposite China's disputed "nine-dash line" maritime claim. While Manila refers to the area as the West Philippine Sea, the Chinese government claims a significant portion of it, which is adjacent to the island of Palawan.

Although President Ferdinand Marcos Jr. has emphasized the economic advantages of trade with China, Manila has consistently filed official protests about Chinese activities within its EEZ. (PIA 5/Keren Anne Bernadas contributed to this report)