0241 GMT May 28, 2018
Planes, boats and helicopters scoured the seas off Japan's Pacific coast in a bid to find the crew who disappeared in the predawn accident, which also left the USS Fitzgerald's skipper injured, AFP reported.
It was not clear where the missing sailors were when the collision happened.
"Search and rescue efforts continue by US and Japanese aircraft and surface vessels in the hopes of recovering the seven USS Fitzgerald (crew) still unaccounted for," the navy said Saturday evening.
The names were withheld until their families have been notified.
Several other crew members were injured and had to be evacuated by air to hospital, including the guided missile destroyer's commanding officer Bryce Benson.
The collision between the Fitzgerald and Philippine-flagged container ship ACX Crystal happened around 2:30 a.m. (1730 GMT Friday) off the coast of the Izu peninsula, southwest of Tokyo.
The damaged ship later sailed back to its base in Yokosuka. The accident happened 104 kilometers (56 nautical miles) southwest of the area, the navy said.
The crash site is a busy shipping channel that is a gateway to major container ports in Yokohama and Tokyo.
"The volume of ships is heavy in this area and there have been accidents before," coastguard official Yutaka Saito told Japan's public broadcaster NHK.