The South China Sea, with its many strategic islands, is one of the biggest maritime routes in the world and has been a flashpoint between China and its neighbors. Naval aggression between the various nations is not new but follows a month of respite.

China's Coast Guard said on Tuesday that four Philippine ships had attempted to enter China's territorial waters around a disputed shoal in the South China Sea. Liu Dejun, a coast guard spokesperson,

China put "lives at risk" with the "unlawful use of water cannons" against Philippine vessels in the South China Sea, the U.S. ambassador in Manila says.

Chinese coast guard vessels, backed by navy ships, have fired powerful water cannons and blocked and sideswiped a Philippine patrol vessel in renewed aggression in a disputed shoal in the South China