Madison police investigating an assault on star Wisconsin running back Montee Ball say they've developed "several persons of interest."
A police statement released Saturday says investigators have determined that a fight occurred a few days prior to the assault. That fight on July 27 involved Wisconsin students, members of the football team and others.
Police say Ball was there but there's no indication he participated in the fight.
Five days later, five men roughed up Ball near campus. Ball suffered a concussion that will keep him out of practice when camp starts Monday.
Police say they're following up on several leads, and that Ball and the school are cooperating fully.
Police Chief Noble Wray says the assault on Ball doesn't appear to be a random attack.