Tribune photo illustration

Chicago Tribune photo illustration (Nancy Stone / Chicago Tribune / February 7, 2012)

The CTA has restored Blue Line train service after a brief overnight service interruption between the between the Rosemont and O'Hare stations.

In an alert on the transit authority's website, officials cited a power issue at the O'Hare station as the cause of the disruption.

Trains experienced residual delays once trains started running again between the stations, but wait times have returned to normal, according to the CTA.

During the service interruption, shuttle buses were in service along the affected portion of the Blue Line.

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