RUMFORD — About 1,900 Central Maine Power customers in Rumford and Mexico lost electricity for an hour or more Monday night, but the cause has yet to be determined, spokeswoman Gail Rice said Tuesday morning.

The power went off in Rumford at 9:37 p.m., flickered off and on a few times and then went out for good at 9:40 p.m.

Alarms could be heard going off at businesses up and down Congress Street, including the Muskie Building, where residents stood lined up on the sidewalk as firefighters investigated.

Lights were on at the NewPage Corp. paper mill in Rumford and at a few stores along Route 2 in Mexico, including Walmart, while houses lining the opposite side of the road were in the dark. Street lights along Route 108 in Rumford remained lit.

Rice said power was restored to 700 customers shortly before 11 p.m. and the rest had power by 11:20 p.m.

“There was no tree down on wires and nothing burnt up,” Rice said.

Line crews checked sections of power lines trying to find a culprit, but found nothing that would cause an outage, so they switched circuits to restore power, she said.

Temperatures were in the high 80s to low 90s at the time, but Rice wasn’t sure if the lines were overloaded with demand from air conditioners and cooling fans.

“I don’t know if it was load or not, but we weren’t doing rolling blackouts or anything like that, and we’re not even close to doing that,” she said.

tkarkos@sunjournal.com