SCRIBA, N.Y. -- Federal officials are trying to pinpoint what sparked a small fire at the Nine Mile One nuclear reactor in Scriba. Flames broke out inside an electrical panel Monday evening. It was quickly put out by workers.

An "unusual event" was declared, the lowest of four emergency classification levels used at nuclear plants. No one was hurt. The reactor did not have to shut down.

The Nuclear Regulatory Commission is helping with the investigation.