BEIJING (AP) — China says it has lost contact with 11 fishermen allegedly taken away by armed men in disputed South China Sea waters.

The official Xinhua News Agency says the men were on the vessel Qiongqionghai 09063 when it was intercepted by armed men who fired warning shots in the air on Tuesday morning near Half Moon Shoal not far from the Philippines.

Xinhua said a second Chinese fishing boat operating nearby outran another boatload of armed men. Two other boats in the area were mobilized to conduct a search, but had turned up nothing by Wednesday morning.

China lays claim to virtually the entire South China Sea and is locked in an increasingly heated dispute with the Philippines, Vietnam and others over rights to energy resources, fishing grounds and island outposts.