US navy stirring up trouble in region's peaceful waters

On Friday, the Ministry of National Defense expressed strong indignation and issued a stern warning after a US warship entered the waters around Chinese islands and reefs in the South China Sea.

The guided missile destroyer USS Mustin was warned away after it entered Chinese waters around China's Nasha Islands without permission.

The latest US move is just one of 11 in the past few years, as the world' sole superpower has been ramping up its "freedom of navigation" operations, which it is using as a pretext for surveillance activities and countering what it claims are China's excessive maritime territorial claims in the waters.