Police in Chacago are seeking a follow-up interview with actor Jussie Smollett amid reports he may have faked a hate-crime assault.

Smollett, 36, a gay African-American actor who appears on hip-hop TV drama Empire, told police he was attacked on January 29 by two masked men who yelled racial and homophobic slurs.

According to Smollett's account, his assailants struck him in the face, draped a rope around his neck and doused him with an "unknown chemical substance" before fleeing.

But the actor now appears to be under investigation himself amid claims he staged the incident because he feared he was about to be written out of the popular television show.

Police say the focus of their investigation has "shifted" after they received new information about the attack from the alleged assailants.

Police detained two Nigerian brothers, identified as Abimbola and Olabinjo Osundairo last week, who were recognised from surveillance footage taken in the area of the alleged assault.

One of the brothers had appeared as an extra on "Empire" and the other was Smollett's personal trainer, whom the actor hired to help get him ready for a music video.