CHICAGO
10/04/2013 12:01 pm ET | Updated Oct 04, 2013

CTA Blue Line Crash Investigation: Sabotage All But Ruled Out, First Lawsuit Filed

AP

Just three days after the "ghost train" collision that injured 33 people on the CTA Blue Line in Chicago, the first lawsuit was filed by a passenger hurt in the bizarre crash.

Meanwhile, the cause of the collision remains under investigation. Despite early reports on Monday speculating that sabotage was a possible factor in the crash, the CTA and National Transportation Safety Board probe has all but ruled that out, according to CBS Chicago.

Instead, investigators appear to be focusing on a technical malfunction causing the mishap, NBC Chicago reports. A bulletin sent Thursday night to CTA employees laid out new procedures to follow to ensure cars taken out of service that end up in a train yard stay put.

In the Monday crash, an unmanned eastbound train struck a westbound train while riding along the same track, overriding a trip mechanism intended to prevent trains from moving out an operator aboard.

The Harlem station, where the crash took place, reopened on Wednesday.

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