Media playback is unsupported on your device Media caption Captain Bryant Fuller from the US Navy: ''The ship's reactor remains in a safe and stable condition''

Seven people have been injured in a fire on a nuclear-powered submarine in the US state of Maine, officials say.

A spokesman for the US Navy says the USS Miami's nuclear reactor was not operating at the time, and is safe.

The blaze started at about 18:00 (22:00 GMT) on Wednesday and was put out in the early hours of Thursday.

The cause of the fire, which affected the forward part of the vessel, has so far not been determined.

The USS Miami has been at the Portsmouth Naval Shipyard on Kittery island in Maine for maintenance work since March.

Officials say five of those injured were firefighters.