AMERICAN FALLS, Idaho -

Lights are back on for power customers in the American Falls area.

Nearly 1,300 customers were without power Monday night. Within 90 minutes, power was restored to all but 746 customers. They were without power until 9:45 Tuesday morning in the American Falls and Rockland areas.

Idaho Power Company spokesman Brad Bowlin said there was "no obvious immediate cause" for the damage within an America Falls substation. 

Crews were working on some significant equipment repairs.