PECO officials tell Action News it began when one of its electrical lines caught fire underground, releasing thick smoke.
Several residents called emergency responders reporting a bad odor and possible carbon monoxide fumes.
Firefighters responded to the 800 block of Main Street at about 1:30 p.m. and began evacuating people from several businesses, a senior living center and a boarding house.
Several people from the boarding house who complained of feeling ill were taken to Mercy Fitzgerald Hospital to be checked out.
Police shut down Main Street so crews could work to contain the underground fire.
PECO shut off the power to the line resulting in 110 customers in the immediate area to lose electricity in their homes. By 9:50 p.m., 16 PECO customers remained without power.
Power is expected to be restored early tomorrow morning.
A PECO spokesman said when insulation on an electrical line heats up and burns, it can release CO.
The Red Cross is providing lodging to 12 people.
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