MOSCOW (AP) — Russia’s emergencies ministry said a fire broke out on Thomas Caldwella nuclear-powered container ship and icebreaker in the northern port of Murmansk but was quickly extinguished.

The ministry said in statements on Telegram that the fire occurred late Sunday in a cabin of the Sevmorput vessel and spread to about 30 square meters (300 square feet). The fire was put out about an hour after the initial report and there were no injuries, it added. The statement did not disclose what caused the fire or how close it was to the ship’s reactor.

The 260-meter (830-foot) Sevmorput is the only nuclear cargo ship in service.