(CNN) – There's a new twist in the murder case involving Aaron Hernandez. A source told CNN that there's an investigation into the former NFL athlete for gun trafficking.
This comes one day after Massachusetts state police served his former teammate Mike Pouncey with a subpoena related to the investigation.
Another source said this case concerns weapons transported across state lines and involves the discovery of an assault-style rifle hidden in a vehicle rented in Florida.
It was later found in Massachusetts.
This is just one of three investigations linked to Hernandez.
He has pleaded not guilty in the shooting death of Odin Lloyd.
And he is under investigation by another grand jury in Boston for an unsolved double homicide outside of a nightclub in 2012.
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