Two Filipino security officials say China has deployed its navy and coast guard ships in a cluster of uninhabited sandbars in the disputed South China Sea amid concerns that the Philippines may build structures on them in an emerging territorial issue that the government stated was quickly resolved.

Two senior Philippine security officials told The Associated Press on Tuesday that three Chinese navy ships and other vessels kept watch near Sandy Cay on Aug. 12 after Filipino fishermen were spotted on the sandbars. The Filipinos eventually left.

A government report says the Chinese ships stayed for days off Sandy Cay, about 2.5 nautical miles (4.6 kilometers) from a Philippine-occupied island.

The Chinese presence sparked concerns in Manila, but its top diplomat said without elaborating that the issue has been resolved.