Rear Adm. Rick Breckenridge, commander of Submarine Group 2 in Groton, Conn., said seven people -- five firefighters and two crew members -- suffered minor injuries in the fire aboard the USS Miami in dry dock at Portsmouth Naval Shipyard in Kittery, Maine, Seacoastonline.com reported. Those injured were treated and released at a hospital.
The cause of the fire had not been determined, Breckenridge said.
He said the damage was confined to forward compartment spaces, including crew living quarters and command and control areas, and the sub's nuclear reactor was never in danger.
There were no weapons aboard, officials said.
Nuclear propulsion spaces "were physically isolated from the forward compartment early during the initial response. The ship's reactor has been shut down for over two months and remained in safe and stable condition throughout the night," Breckenridge said.
The propulsion spaces "remained habitable and were continuously manned throughout the night," he said.
Shipyard firefighters had been called at 5:41 p.m. Wednesday and the fire went to four alarms just after 10 p.m.
The USS Miami, with a crew of 13 officers and 120 enlisted personnel, arrived at the shipyard March 1 for maintenance work and system upgrades.
The 360-foot sub was commissioned in June 1990.