China said it was "very displeased" after a U.S. Navy destroyer conducted a so-called freedom of navigation patrol (FONOP) within 12 nautical miles (22 km) of an artificial island built up by China in the South China Sea.

The operation, which involved the Yokosuka, Kanagawa Prefecture-based USS John S. McCain guided-missile destroyer, was conducted Thursday around Mischief Reef in the Spratly chain of the strategic waterway, and was first reported by Reuters, citing anonymous U.S. officials.

China's Foreign Ministry confirmed the patrol, saying that the operation had violated international and Chinese law and seriously harmed Beijing's sovereignty and security, adding that the Chinese Navy had "warned and expelled" the U.S. warship.