US sailors to be blame in Cargo ship collision.

US crew members were found dead in damaged parts of the ship. Most of the crew would have been asleep at the time of the crash.

The crew of a Navy destroyer that collided with a Philippine-flagged cargo ship will "certainly" be held accountable for the crash that killed seven American sailors, a US defense official said Friday.

"The way it looks now, it seems that the crew on the (USS) Fitzgerald is going to be at fault," the official said on condition of anonymity.

"They are certainly going to be held accountable in some way for their actions," the official added.

"This is something we take very seriously. There are seven sailors that lost their lives."

Senior spokeswoman Rear Admiral Dawn Cutler stressed the investigation was still in its "early stages" and said it was too soon to release any definitive information.

"It is premature to speculate on causation or any other issues," Cutler said in a statement.

The defense official said the probe would likely be released in about a month.

The sailors were killed in a June 17 predawn collision between the USS Fitzgerald and the Philippine-flagged ACX Crystal in a busy shipping channel off Japan's coast.

Aged 19 to 37, the seamen were found by divers in flooded sleeping berths a day after the collision tore a huge gash in the side of the USS Fitzgerald.

There have been around 30 ship collisions over the past decade in the busy shipping area, including a 2013 incident in which six Japanese crew members died, according to the Japan Coast Guard.