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San Onofre nuclear plant has low-level malfunction

One of the security systems used to monitor the San Onofre nuclear plant stopped working Saturday morning.

July 16, 2011 12:00:00 AM PDT
One of the security systems used to monitor the San Onofre nuclear plant stopped working Saturday morning.

Utility officials said an "unusual event" was declared at 6:12 a.m., triggering a low-level emergency. The system was restored by 7 a.m.

A spokesperson said the malfunction was not related to nuclear operations and no part of the plant's perimeter was left unguarded.

It is unclear what equipment was affected. Nuclear plant officials are investigating the cause of the incident.

The Associated Press contributed to this story