CHICAGO (WBBM) – A Mylar balloon is to blame for hundreds of power outages on Chicago’s north side.

About 700 ComEd customers were without power for a few hours after a Mylar balloon caused a power outage for Roscoe Village residents during the kick-off of the popular music fest, Retro on Roscoe.

LISTEN: WBBM Newsradio’s Lisa Fielding Reports

Around 11 a.m., power was initially knocked out after a Mylar balloon came in contact with electric wires at Cornelia and Western…an hour later, 70 percent had been restored. The outages were initially reported from Addison to Roscoe to Ravenswood to Western. The utility is reminding residents not to let go of balloons.

Retro on Roscoe runs through the weekend.

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