

While Chicago police try and determine whether Jussie Smollett orchestrated his alleged last attack last month, the FBI is still investigating the other incident involving Smollett, which could result in federal charges no matter what.

Two days before the alleged attack on Smollett, a letter containing white powder was sent to the set of "Empire." The substance was later determined to be aspirin.

Smollett described the letter during his "Good Morning America" interview with Robin Roberts, saying, "It had a stick figure hanging from a tree with a gun pointing toward it with the words that says Smollett Jussie, you will die."

According to our sources, the FBI is investigating who sent the letter, regardless of whether or not the threat was legitimate or part an elaborate set-up involving Smollett.

Our sources say the feds are looking at both possibilities and are simply working to find out whoever sent the threatening letter, period.

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We're told the possible charge would be "mailing threatening communications," which states:

Whoever knowingly so deposits or causes to be delivered as aforesaid, any communication with or without a name or designating mark subscribed thereto, addressed to any other person and containing any threat to kidnap any person or any threat to injure the person of the addressee or of another, shall be fined under this title or imprisoned not more than five years, or both.

Legally, if reports are true and somehow the letter send is a part of some hoax or setup, whoever is responsible can be arrested.

Jussie Smollett's legal team released a statement on Saturday night saying, "As a victim of a hate crime who has cooperated with the police investigation, Jussie Smollett is angered and devastated by recent reports that the perpetrators are individuals he is familiar with."

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The statement continued, "He has now been further victimized by claims attributed to these alleged perpetrators that Jussie played a role in his own attack. Nothing is further from the truth and anyone claiming otherwise is lying."

“One of these purported suspects was Jussie’s personal trainer who he hired to ready him physically for a music video,” the statement concluded, adding, “It is impossible to believe that this person could have played a role in the crime against Jussie or would falsely claim Jussie’s complicity.”