The Chinese People's Liberation Army (PLA) expelled a U.S. destroyer when the latter trespassed into Chinese territorial waters off the Xisha Islands in the South China Sea on Thursday amid continued U.S. attempts to destabilize the region.

Without authorization from the Chinese government, guided missile destroyer the USS Milius on Thursday made an illegal intrusion into Chinese territorial waters off the Xisha Islands, sabotaging the peace and stability in the South China Sea, Senior Colonel Tian Junli, a spokesperson at the PLA Southern Theater Command, said in a press release on the day.

The PLA Southern Theater Command organized naval and air forces, tracked, monitored and warned away the U.S. warship in accordance with the law, Tian said.

Command troops will stay on high vigilance at all times and take all necessary measures to resolutely safeguard national sovereignty, security as well as peace and stability in the South China Sea, the spokesperson said.

Launching an immediate response, the PLA displayed that it is ready at all times to counter foreign provocations, including those from the U.S., Song Zhongping, a Chinese military expert and TV commentator, told the Global Times on Thursday.

The U.S. has been ramping up provocations on China’s doorstep, attempting to conduct close-in reconnaissance on China and to deny China of its sovereignty and jurisdiction over the Xisha and Nansha islands, showing U.S. military presence and hegemony in the South China Sea, Song said.

But the PLA will not give an inch when it comes to territorial integrity, Song added.

In late February, a U.S. P-8A spy plane took a group of U.S. reporters on a close-in reconnaissance operation over the South China Sea, during which it was warned away by a PLA fighter jet when it came close to Chinese airspace around the Xisha Islands.

This latest U.S. warship trespass and the P-8A media tour are a combo move aimed at hyping “China threat” in the South China Sea and throwing mud at China, Song said.

From a military point of view, these types of close-in reconnaissance operations are also carried out under a tactical consideration in preparation for potential military conflict, the expert warned.

The world should see clearly that the U.S. is the real trouble maker in the South China Sea, multiple observers noted.