Smollett, 36, who is black and openly gay, reported to police on January 29 that two men beat him while he walked downtown in the third-largest American city.
He alleged they yelled racial and homophobic slurs, poured bleach on him and tied a rope around his neck, prompting police to initially describe the case as a possible hate crime.
Earlier on Friday police spokesman Anthony Guglielmi said detectives had “probable cause” that two men arrested may have been involved in an alleged offense.
But late the same day, Tom Ahern, the police Deputy Director of News Affairs and Communications, said on Twitter that “the individuals questioned by police in the #Empire case have now been released without charging and detectives have additional investigative work to complete.”
He said the step followed “new evidence as a result of today’s interrogations.”
Police initially announced the arrest of the two men after US media reported that investigators were probing the possibility that the attack was staged.
Guglielmi, however, told AFP “there is no evidence” to say it was a hoax.
Multiple US media outlets reported the two men are brothers who were arrested at Chicago’s O’Hare airport upon return from a trip to Nigeria. At least one of the men reportedly worked on “Empire,” a series about the fortunes of an ailing hip-hop mogul and his family battling over control of a multi-million dollar music company.
Smollett has expressed anger over rumors and speculation reported in the media doubting his account.
Initial reports of the attack shocked the entertainment industry and brought waves of support from advocacy groups.
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