A sixth US warship is now operating in the eastern Mediterranean, near five US destroyers armed with cruise missiles that could soon be directed against Syria as part of a "limited, precise" strike, defence officials said late on Friday.
They stressed that the USS San Antonio, an amphibious ship with several hundred U.S. Marines on board, was in the region for a different reason and there were no plans to put Marines on the ground as part of any military action against Syria.
"It's been kept there as a precaution," said one of the officials, who was not authorized to speak publicly.
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