CHICAGO (CBS) — Cell phone GPS records helped make the case against a 44-year old man accused of taking part in a big gun theft from a freight train on the Southeast Side.

As a result, federal gun charges have been filed against two men in connection with the theft of 111 weapons from a Chicago rail yard.

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Court records show 44-year-old Alexander Peebles and 48-year-old Warren Gates were charged with possession of a firearm by a prohibited person.

According to the complaint filed in U.S. District Court, an investigation in the theft in April determined eight other people were involved in the April theft.

Authorities say there were 318 firearms from a Ruger factory shipment in the freight car at the time of the theft.

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Authorities say they were led to the men by an arrest that occurred during another theft attempt at the rail yard.

Gates was ordered held Wednesday pending a detention hearing.

Peebles was freed on bail.

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