The Chinese People's Liberation Army (PLA) expelled a U.S. guided-missile destroyer after it trespassed into China's territorial waters near the Xisha Islands in the South China Sea, PLA Southern Theater Command spokesperson Tian Junli said in a statement released on Monday. 

Tian said the U.S. military's act has seriously undermined China's sovereignty and security interests, damaged the peace and stability in the South China Sea region, and violated the international law and basic norms governing international relations.

It's another proof of American hegemony, he stressed, adding that this also proves that the U.S. military is the source of security risks in the South China Sea region.

Tian said China strongly condemned and opposed the U.S. act and urged the country to stop such proactive actions.

The theater command will "remain on high alert, and take all necessary measures to fulfill its duty of protecting national sovereignty and security, as well as peace and stability in the region," said Tian.