CHICAGO (WLS) -- An Indiana man returned to court on Monday.
He allegedly sold a gun that ended up with one of the suspects accused in the murder of Chicago Police Officer Areanah Preston.
Corey Gray was in a Dirksen Federal Building court room for a hearing about his bond. Federal prosecutors allege Gray crossed state lines to illegally sell the gun for $1,200.
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The prosecutor, Paul Schied, argued, "He made a profit by selling a weapon into Chicago's underworld."
Last week, thousands of officers and civilians honored the 24-year-old officer. Preston was killed after she returned home after her shift as the result of an armed robbery on May 6.
Four teens have been charged. Prosecutors said during the arrests, the weapon, connected to Gray, was found.
On Monday, prosecutors argued that Gray should remain in federal custody, as he is accused of robbing an Indiana couple during a gun sale. They also argued that Gray has a home electronic monitoring violation while he's been out on bail for that Indiana case.
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"This case sadly demonstrates the seriousness of this charge," said Federal Judge Beth Jantz. "This is a grave illustration of the nature of this case in our community."
With that, she ordered that Gray remain in custody pending the outcome of this case.