Transcript for 7 sailors remain missing off the coast of Japan after Navy destroyer collides with a tanker

start here with the developing story overseas involving that U.S. Navy destroyer. Seven sailors missing right now after their ship collided with a tanker off the coast of Japan. Questions abound as to how this could have happened. We want to you look at this video of "Uss Fitzgerald" limping back into port in Japan. This as U.S. And Japanese ships and aircraft are frantically conducting search and rescue missions. Five people were medevacked off the boat. We'll kick off our coverage with ABC's Matt Gutman reporting from Los Angeles. Matt, good morning to you. Reporter: Good morning, Dan and Paula. Hard to overstate how serious an incident this was. The Navy is still searching for those seven missing sailors. They have multiple search planes scouring the water, but because of the damage you just saw it's so severe it's also possible those sailors could still be in the wreckage on board. Just minutes ago we learned that a total of five sailors had to be medevacked including the commander of the ship. This morning the "Uss Fitzgerald" has been tugged back to port but at least seven sailors remain missing. The Navy saying multiple sailors were injured in the monstrous collision with the container ship, five sailors hurt badly enough they had to be medevacked. One of them the ship's commanding officer. The Japanese coast guard leading the initial rescue. You can see responders crowded near the wreckage to extract the wounded. Helicopter footage shows the destroyer's mangled midsection, the damage caving in compartments, destroying ship machinery and its radio room. The Navy saying damage both above and below the water line caused major flooding. Those red hoses seen pumping seawater out of the belly of the ship which typically has a crew of nearly 300. The Navy says this 30,000-ton container ship and the much smaller 9,000-ton U.S. Destroyer collided in open water 56 miles southwest of yokosuka, Japan. The Navy telling ABC news this morning that the extent of the personnel injuries aboard the ship is still being assessed. Now, there are two major questions going forward. Which of the ships had the right of way and perhaps a bigger issue that even though it was the dead of night, how did a ship with some of the most sophisticated radar and sonar on the planet neither see or manage to avoid something the size of a small island bearing down on it. Dan, Paula. Questions we'll be addressing in just a moment. Thanks for your reporting. Joining us now from Washington is retired marine colonel and ABC news contributor Steve ganyard. Steve, good morning to you. You just heard Matt's question, the most glaring one that we all have, these ships aren't traveling swiftly on one another's radar. How could a collision have happened? It's hard to imagine how it could have. As Matt said two sophisticated ships and they should have seen each other. On the other hand this happened really just about ten miles outside of the mouth of Tokyo bay which is one of the busiest ports in the world. It was the middle of the night and so oftentimes what happens in these collisions at sea it's a series of mistakes on both ships that lead to a tragic event. We are as everybody knows at a time of heightened fears over North Korea. What kind of impact could taking a destroyer like this out of commission, what kind of impact could that have on our ability to defend ourselves and allies. It's one of the most sophisticated ships and has a special radar and special set of missiles that could intercept atmospherically in space any kind of north Korean missile that may be shot at Japan or South Korea or U.S. Bases in the region so the Navy is going to want to backfill this quickly because the "Fitzgerald" will be out of service for a long time. Thank you.

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