"Tonight, CPD (Chicago Police Department) arrested the first of several juvenile offenders in the Facebook sexual assault incident," the department's chief spokesman Anthony Guglielmi said on Twitter, adding that a news conference would provide further details on Sunday.
The mother of the victim of the March assault had approached police after an unrelated news conference and shown them images of her daughter being assaulted by five or six young men.
The mother said the girl's uncle had told her about a video on Facebook Live that showed the assault. The high school freshman had gone to the store and her mother became concerned when she did not return.
The March incident was among several in recent months in Chicago in which the social media site has played a role in broadcasting apparent crimes.
The shooting death in February on the city's West Side of a 2-year-old boy was captured on Facebook Live by his aunt, who was also shot. In January, an attack by four people on a 19-year-old man with special needs was partially broadcast on the social media site. The four accused in the attack have pleaded not guilty.
(Reporting by Chris Michaud in New York; Editing by Randy Fabi)
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)