The U.S. is once again challenging China's "unlawful" claims in the South China Sea with the transit of a U.S. Navy destroyer through the contested waters. The U.S. Navy conducted a Freedom of Navigation Operation (FONOP) near the Paracel Islands on Thursday, immediately drawing a response from China.

The U.S. Navy destroyer USS Benfold took part in the operation, which U.S. officials said was part of their normal operations in international waters. Like previous FONOPs, China didn't respond well to the operations, stating that it was a clear violation of its sovereignty and national security.

U.S. Navy officials argued that it is merely defending every nation's right to sail and operate through international waters without breaking international laws. Officials said nothing China would say would deter them from conducting further FONOPs.

In an official statement, the U.S. Navy made its intentions clear and said that China's continued "unlawful" claims in the South China Sea poses a serious threat to the freedom of navigation, free trade, commerce, and freedom of economic opportunity for the nations also laying claim to the contested territories. The latest transit is yet another challenge to China's "excessive" maritime claims, which the U.S. intends to continue to do.  

China's military responded by alleging that the USS Benfold had trespassed through its territory around the Xisha Islands, which China calls the Paracel Islands. Chinese officials said the continued operations are destabilizing the peace in the region.

Chinese air force colonel and spokesperson for the People's Liberation Army Southern Theater Command Tian Junli demanded that the U.S. immediately stop their "provocative actions." He then threatened that further actions could result in "serious consequences."

Chinese officials said the PLA Southern Theater Command is now on high alert, and it is prepared to take "resolute actions" against any further incursions to safeguard the nation's sovereignty and national security while also protecting the peace and stability in the region.

The Chinese military claimed to have tracked and monitored the USS Benfold and warned it off from its territory. U.S. Navy officials denied the claims, stating reports that Chinese vessels had warned it off were "false." The U.S. Navy stressed in its statement that the operation was in accordance with international law.

The Paracel Islands is one of many contested groups of islands in the South China Sea. The islands are also being claimed by neighboring countries such as Vietnam. China maintains full maritime control of the islands and the surrounding seas through its more than 20 outposts in the area.