The train was suspended between O'Hare and Rosemont due to "fire department activity" near O'Hare around 6:18 a.m.
Chopper 7 was over the tracks near O'Hare airport and did not see anything on the tracks.
It is unknown why the fire department was working in the area.
Service resumed with minor delays around 7:20 a.m., according to CTA.
Trains were only operating between Forest Park and Rosemont, causing some delays for morning commuters.
Shuttle buses were requested to help passengers commute.
The video in the player above is from a previous report.
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