RUMFORD — Power outages were expected through the night Monday as crews from Central Maine Power Co. worked to isolate the cause of random electrical failures plaguing the area for the past several days.

A spokesperson for the power company said crews initially thought the outages were due to a failed insulator that was repaired Sunday after power went out in the area for the second time in as many days. The outage left about 1,910 customers without power for around 90 minutes.

When the Rumford, Mexico and part of Dixfield lost power again Sunday, the spokesperson said Central Maine Power decided to test every line in the area to discover the exact cause of the problem.

The spokesperson said that customers could expect power outages off and on throughout the night as crews shut down lines to test them.