A U.S. Navy guided-missile destroyer collided with a Philippine-flagged cargo ship off the coast of Japan early Saturday, with at least three members of the destroyer's crew — including its commander — requiring medical evacuation and leaving seven sailors missing.

The cause of the collision, which occurred 56 nautical miles (103 km) southwest of Yokosuka, Kanagawa Prefecture, remained unclear.

The damaged USS Fitzgerald limped home to its Yokosuka home port around 6 p.m., where it would be further inspected, according to the U.S. Navy's 7th Fleet. Search and rescue efforts by U.S. vessels and aircraft, as well as ships from the Japan Coast Guard and Maritime Self-Defense Force, continued the hunt for the seven missing sailors. Their names are being withheld until the families have been notified.