BEIJING - Naval and air units of the People's Liberation Army Southern Theater Command on Sunday conducted combat readiness patrols in the territorial waters and airspace of China's Huangyan Dao and its surrounding areas.

Stressing that Huangyan Dao is an inalienable part of China's territory, the command said in a statement that its naval and air forces have enhanced readiness patrols there since March, and carried out tracking, monitoring, warning and expelling operations in accordance with laws and regulations.

"Such patrols serve as an effective countermeasure to cope with all sorts of rights-violation and provocative acts," it said.

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Also on Sunday, the China Coast Guard (CCG) conducted law enforcement patrols in the territorial waters of Huangyan Dao and its surrounding areas.

In a statement, the CCG said it has intensified law enforcement patrols in the territorial waters of Huangyan Dao and surrounding areas since March, and regulated ships engaged in illegal rights-violation activities in accordance with laws and regulations.

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"Such patrols are meant to further strengthen orderly management of relevant waters and resolutely safeguard China's territorial sovereignty and maritime rights and interests," it said.