The US littoral combat ship USS Charleston intruded into waters near Xianbin Reef in China's Nansha Islands without the permission of the Chinese government in the early hours of Tuesday. This prompted the Chinese People's Liberation Army Southern Theater Command Navy to deploy forces to track and monitor the vessel in accordance with the law and regulations, the theater command said on Tuesday.

Yin Gang, a spokesman for the PLA Southern Theater Command Navy, stated that China has indisputable sovereignty over the Nansha Islands and their adjacent waters.

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"The US action infringed on China's sovereign rights and interests, threatened maritime security, and undermined regional peace and stability. The US should immediately cease such activities," Yin said.

The theater command's forces remain on high alert to safeguard national sovereignty and security and maintain regional peace and stability, he added.