Update:

As of 9:20 p.m., power had been restored to all customers affected by the outage, according to Met-Ed's outage center.

By 8 p.m., all customers in Conewago Township had their power restored. At the same time, 85 customers in Manchester Township were without power.

A call to a Met-Ed spokeswoman was not returned.

Previously reported:

More than 3,500 Met-Ed customers are without power Monday evening.

The majority of customers are in Manchester and Conewago townships, according to Met-Ed's outage center.

In Manchester Township, 1,792 customers are reported to be without power while 1,363 customers in Conewago Township don't have electricity as of 7 p.m.

A number of traffic signals have also stopped working due to the outage.

Some sort of power surge is believed to be the cause for the outage, according to York County 911 radio transmissions.

Check back later for additional details.