The Southern Theater Command of the People's Liberation Army and the China Coast Guard conducted drills in sea and airspace around China's Huangyan Island on Saturday.

The theater command organized joint naval and air exercises in the territorial waters and airspace of Huangyan Island and its surrounding areas, it said in a statement. The drills focused on realistic combat scenarios, including reconnaissance and early warning, deterrence patrols, sea and air control, and joint strikes, the statement said, adding that these exercises effectively tested the forces' capabilities in sea-air coordination, rapid support, and integrated operational success.

"Huangyan Island is an inherent part of Chinese territory, and the so-called territorial sea baseline set by the Philippines is illegal and invalid," it said. "The theater forces remain on high alert, resolutely defending national territorial sovereignty and maritime rights."

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On the same day, the China Coast Guard conducted rights protection enforcement exercises in the waters near Huangyan Island, Jiang Lue, spokesperson for the CCG, stated in a statement.

The exercises focused on enforcement actions such as visit, board, search and seizure, intercepting intrusions, and forcibly towing away vessels, he said.

"Huangyan Island is an inherent part of Chinese territory. The China Coast Guard will intensify rights protection enforcement and control efforts in the waters near Huangyan Island, firmly safeguarding national territorial sovereignty and maritime rights," Jiang said.