The commander of the USS Fitzgerald is also hurt. Photograph: (Reuters)
Seven crew members are missing and three have been injured after a US Navy destroyer collided with a merchant vessel off the coast of Japan.
The injured included the ship's commanding officer, Cmdr. Bryce Benson.
All three of the injured were medically evacuated.
The Japanese Coast Guard said the destroyer was taking on water but was in no danger of sinking, while the merchant vessel was able to sail under its own power.
In a statement, the US Navy said the USS Fitzgerald collided with a merchant vessel 56 nautical miles southwest of Yokosuka.
A US official, speaking on condition of anonymity, said the destroyer had suffered damage, that there was some flooding, and that it could not operate on its own power.
Japan's public broadcaster NHK showed aerial footage of the destroyer, which had a large dent in the right side of the ship.
Images broadcast by NHK showed the US ship has been struck on its starboard side next to its Aegis radar arrays behind its vertical launch tubes.
No apparent damage could be seen from the images below the waterline although damage on the deck and to part of the radar appeared significant.
NHK said that the commercial vessel is a Philippines container ship. A spokesman for the Philippines coast guard said he had heard of the accident but had no details since it was not in Philippine waters.
The US Navy said it had requested the assistance of the Japanese Coast Guard.
Such incidents are rare.
In May, the US Navy's USS Lake Champlain collided with a South Korean fishing vessel but both ships were able to operate under their own power.
Situated at the approach to Tokyo bay, Yokosuka and the waters to its south are a busy commercial waterway plied by commercial vessels sailing to and from Japan’s two biggest container ports in Tokyo and Yokohama.