A U.S. Navy destroyer sailed near one of the most important man-made and Chinese-controlled islands in the South China Sea on Monday, in a freedom of navigation mission that Beijing denounced as illegal.

While the United States frequently makes such voyages to challenge China and other states' territorial claims in the strategic waterway, the latest one took place as Beijing staged more war games around Taiwan.

The U.S. Navy's 7th Fleet said the USS Milius engaged in "normal operations" within 12 nautical miles of Mischief Reef in the Spratly Islands, once a reef submerged at high tide and where China has built an airport and other facilities.