US Navy destroyer conducts operation in South China Sea

This image provided by the U.S. Navy, taken Oct. 17, 2016, shows the guided missile destroyer USS Decatur, right, pulling into position behind the Military Sealift Command USNS Matthew Perry, during a replenishment-at-sea, seen from the bridge of the guided-missile destroyer USS Spruance, in the South China Sea. The Defense Department says a U.S. Navy warship has conducted a freedom of navigation operation in the South China Sea, where China and five other countries have competing territorial claims. A department spokesman, Navy Cmdr. Gary Ross, said the destroyer ship USS Decatur conducted the transit operation Friday, Oct. 21, 2016, near the Paracel Islands. (U.S. Navy/Petty Officer 2nd Class Will Gaskill via AP) (The Associated Press)

This image provided by the U.S. Navy, taken Oct. 17, 2016, shows the guided missile destroyer USS Decatur, right, pulling into position behind the Military Sealift Command USNS Matthew Perry, during a replenishment-at-sea, seen from the bridge of the guided-missile destroyer USS Spruance, in the South China Sea. The Defense Department says a U.S. Navy warship has conducted a freedom of navigation operation in the South China Sea, where China and five other countries have competing territorial claims. A department spokesman, Navy Cmdr. Gary Ross, said the destroyer ship USS Decatur conducted the transit operation Friday, Oct. 21, 2016, near the Paracel Islands. (U.S. Navy/Petty Officer 2nd Class Will Gaskill via AP) (The Associated Press)

The Defense Department says a U.S. Navy warship has conducted a freedom of navigation operation in the South China Sea, where China and five other countries have competing territorial claims.

A department spokesman, Navy Cmdr. Gary Ross, said the destroyer ship USS Decatur conducted the transit operation Friday near the Paracel Islands.

He said it was conducted "in a routine, lawful manner without ship escorts and without incident."

The U.S. Navy has periodically conducted such freedom of navigation operations in the South China Sea.

Ross said the operation "demonstrated that coastal states may not unlawfully restrict the navigation rights, freedoms and lawful uses of the sea" that all states are entitled to exercise under international law.

Vietnam, China and Taiwan all claim the Paracel islands, which are occupied by China.