A US Navy Aegis cruiser collided with a nuclear-powered submarine during exercises off the East Cost on Saturday (local time), collapsing the sonar dome on the cruiser and possibly causing other damage, but no injuries, US Navy officials say.
The collision between the USS San Jacinto and the nuclear-powered submarine USS Montpelier occurred about 3.30pm, the navy said in a statement. The navy declined to say where off the East Coast the accident occurred.
A navy official said the watch team aboard the San Jacinto saw a periscope rise from the water about 100 to 200 metres ahead of the vessel during the exercise. The cruiser ordered "all back", but the San Jacinto still collided with the submarine.
The collision caused the collapse of the cruiser's sonar dome, a bulbous-shaped device on the bow of the ship beneath the water line, the navy official said on condition of anonymity.
The rubber dome houses some of the vessel's electronic navigation, detection and ranging equipment.
The navy said no personnel were injured during the incident and there was no damage to the submarine's nuclear-powered propulsion plant. Both vessels were operating under their own power.
The ships were part of a strike group led by the aircraft carrier USS Harry S Truman. The Truman was in the area and providing support to the vessels.
The incident is being investigated, the navy said, and overall damage to both ships is still being evaluated.