The Armed Forces of the Philippines (AFP) on Sunday commended the civilian-led “Atin Ito” coalition for its mission to Pag-asa Island, as the Philippine Coast Guard (PCG) moved to challenge and drive away Chinese research vessels operating in Philippine waters.

Rear Adm. Roy Vincent Trinidad, AFP spokesperson for the West Philippine Sea, said the mission—culminating in the raising of the Philippine flag on Sandy Cay—was a “powerful assertion” of the country’s sovereign rights.

“This is not merely a symbolic gesture; it is a demonstration of active citizenship in the face of external challenges,” Trinidad said.

He added that the initiative reinforces the Philippines’ claim in the West Philippine Sea and highlights the importance of protecting the livelihood of coastal communities.

The AFP reiterated its commitment to support peaceful, rules-based actions anchored on the 2016 Arbitral Award.

Meanwhile, the PCG said it has deployed aircraft and vessels to challenge four Chinese research vessels detected within the country’s maritime domain.

PCG spokesperson Commodore Jay Tarriela said the vessels were monitored using Canada’s Dark Vessel Detection System and were believed to be conducting unauthorized marine scientific research without Philippine consent.

“This is in clear violation of UNCLOS,” Tarriela said.

The vessels identified include advanced oceanographic and deep-sea research ships, with capabilities ranging from seafloor mapping to the deployment of unmanned underwater systems.

PCG Commandant Admiral Ronnie Gil Gavan said the agency will continue to assert the country’s sovereign rights.

“We will not tolerate any illegal marine scientific research conducted without our government’s consent,” Gavan said, adding that operations are being carried out in line with national and international law.