ComEd employees are investigating the cause of a massive power outage that took place early Wednesday afternoon that left an estimated 30,000 customers without power in Kendall County and portions of Will and Kane counties.

Crews are still exploring and investigating the cause of the outage, though it was believed to be due to a downed power line, according to ComEd.

Officials at ComEd reported their employees began receiving reports of outages from customers around 1:45 p.m. affecting Oswego, Montgomery, Aurora, Yorkville and Plainfield. By 3:20 p.m., officials said that power had been restored to all affected customers.

Several local public agencies were affected by the outage, including all facilities of Oswego-based School District 308 and the Yorkville Public Library.

Joshua Flanders of the Oswego Fire Protection District said no injuries were reported in the fire district due to the outage, though firefighters responded to multiple calls of carbon monoxide detectors, fire alarms, and elevator alarms malfunctioning due to the loss of power.

Oswego Police Department Public Information Officer Cathy Nevara reported said all roadway intersections had been restored to power around 3:15 p.m., though at the time some homes and businesses were still experiencing intermittent outages at the time.

The Montgomery Police Department also confirmed that no accidents were caused by the outage, though officials did respond to calls regarding malfunctioning smoke detectors and carbon monoxide detectors.

Deputy Chief Terry Klingel of the Yorkville Police Department said no accidents or injuries were caused by the outage, though officers did respond to a carbon monoxide detector malfunction believed to be caused by the outage.