CTA trains experienced major delays Thursday morning due to switching problems near Clark and Lake.
Several Brown and Purple Line trains were diverted to the Red Line subway, and Orange, Green and Pink Line trains were cut short on their routes.
The Red, Blue and Yellow lines all were operating normally during the delay, according to the transit agency.
As of 10:30 a.m., CTA officials said most trains were resuming normal service, though there could be some "significant" residual delays along with heavy train congestion on Pink, Green, Brown, Orange and Purple Line Express Trains.
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