CHICAGO (CBS) — Service has been restored after a long section of the third rail on the CTA Blue Line fell over near Jefferson Park Friday morning, CTA officials say.

Crews work to repair a broken rail on the CTA Blue Line on Feb. 1, 2019. (Credit: Brian Steele, CTA)

A “lengthy section” of the third rail was knocked off its supports and onto the ground, causing trains to stop between 30 and 45 minutes, according to the CTA.

Trains have now started running again, but are operating on a single track between Harlem and Montrose, causing continued delays. Passengers should board all trains on the O’Hare-bound side at Jefferson Park.

A bus shuttle is also available between O’Hare and Jefferson Park.

Some trains may turn back before the end of the line to maintain service, the CTA said in a Tweet.

Crews are working on repairs and hope to have the issue fixed by afternoon.