Najee Ali, who is also the director of Project Islamic HOPE, said false claims make real incidents of racist attacks and homophobia easier to dismiss.
"It's a slap in the face. We have many members of the black community and the LGBTQ community who have been the victims of racism and hate crimes, so for Smollett to say that he was a victim...and we believe is a lie...certainly is an injustice to those true victims...," Ali said. "Jussie Smollett must be brought to justice for lying."
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Ali said Smollett's story was given the benefit of the doubt at first, but over the last few days, the "campaign of lies continued to be unraveled."
Smollett, who is black and gay, has said he was physically attacked last month by two masked men shouting racial and anti-gay slurs and "This is MAGA country!" He said they looped a rope around his neck before running away as he was returning home from an early morning stop at a Subway restaurant in downtown Chicago. He said they also poured some kind of chemical on him.
RELATED: Timeline of key moments after alleged attack on Jussie Smollett
Police said they combed surveillance video in the heavily-monitored area but were unable to find any footage of the attack. They did obtain images of two people they said they would like to question.
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On Wednesday, Chicago police picked up the brothers at O'Hare International Airport as they returned from Nigeria. They described them as "suspects" in the assault, questioned them and searched their apartment.
Then, late Friday evening they released the two men without charges and said they were no longer suspects. They said they had gleaned new information from their interrogation of them.
Smollett's lawyers said late Saturday that the actor felt "victimized" by reports that he played a role in the assault, adding that, "Nothing is further from the truth and anyone claiming otherwise is lying." The statement from attorneys Todd Pugh and Victor P. Henderson also said Smollett would continue cooperating with police.
The Associated Press contributed to this report.
WATCH: Bottle that smelled like bleach found near Smollett attack location