A Chinese military spokesperson on Thursday called the trespassing of a U.S. warship into China's territorial waters a serious provocation.
Earlier in the day, the U.S. missile destroyer USS Benfold sailed into waters off the Xisha Islands in the South China Sea without permission from the Chinese government.
Wu Qian, spokesperson for China's Ministry of National Defense, said this is not "freedom of navigation" as claimed by the United States but an act that has violated China's sovereignty and undermined the peace and stability of the South China Sea.
Wu said the People's Liberation Army has dispatched air and naval forces to monitor the U.S. warship and warn it off.
"The Chinese military strongly deplores and resolutely opposes the U.S. act," he said, adding that the U.S. military warship's hegemonic behaviors can not be tolerated in China's territorial waters.
Wu urged the U.S. side to understand the situation clearly and stop provocation.
The Chinese military will take all necessary measures to respond to any threats and provocations, and will resolutely protect China's sovereignty and security and safeguard regional peace and stability, he said.