Xcel Energy says its nuclear power plant at Prairie Island near Red Wing was being shut down earlier this morning after a fire alarm was activated in the unit two containment building.

There was no indication of a fire but plant personnel decided to shut the plant down until the issue was resolved. Spokesman Tom Hoen says there was no release of radioactive materials as a result of this event, which was reported around 4 a.m.

Additional details about the incident will be provided when they become available.