The standoff over Sandy Cay, which lies close to military outposts built by both Beijing and Manila, was the latest between the two nations.

China and the Philippines have each unfurled their national flags on tiny sandbars in the South China Sea, staking competing sovereignty claims in strategic waters seen as a potential flashpoint for global conflict.

China's coast guard said Sunday it had "dealt with" a situation involving six Filipinos who it accused of illegally landing on a disputed reef, after Beijing's state media said the tiny sandbank had recently come under Chinese control.