Hamilton County prosecutor Joe Deters said in a statement that his office would determine whether any criminal charges were appropriate. He declined further comment.
Deters didn't specify what charges would be considered, but possible charges could include assault and battery or disorderly conduct. A spokeswoman said he hadn't set a timetable for a decision.
A Xavier spokeswoman said it would be premature to comment on Deters' investigation. The UC athletic department didn't comment immediately, but scheduled an afternoon news conference to discuss the brawl.
Criminal prosecutions from player confrontations during sports events are rare. A handful of National Hockey League players have been charged with assault over the years. Detroit Red Wings forward Todd Bertuzzi pleaded guilty to assault after he, while playing for Vancouver in 2004, sucker-punched Colorado's Steve Moore on the ice. No one was charged after a 2010 baseball brawl in Cincinnati in which St. Louis Cardinals catcher Jason LaRue suffered a career-ending concussion after being kicked in the head by Reds pitcher Johnny Cueto.
Officials and coaches for both universities have offered apologies and expressed embarrassment. Each team also suspended four players.
Cincinnati's Yancy Gates received the longest suspension, six games. Gates punched Xavier's Kenny Frease, causing a gash that left him bleeding below his left eye, and hit at least one other Xavier player during the fracas.
Frease also was kicked as the two teams converged on each other. X-rays of Frease after the game were normal.
Xavier guard Tu Holloway, who acknowledged making comments directed at UC's team right before the brawl, caused a stir by later describing his team's toughness as "a whole bunch of gangsters." Holloway, suspended for one game, said Sunday he regretted using the term "gangsters."
Xavier, ranked No. 8, won the game on its home court, 76-53, but the focus after the "Crosstown Shootout" was on the brawl, which was televised live on ESPN and has been reshown a myriad of times on TV and online.
"It's literally and figuratively a black eye," said Raymond Buse, a veteran publicist here. "I was in disbelief that this was happening in Cincinnati. Typically, this is great spirited, one of the greatest rivalries in college basketball.
"Now the national public just sees our 15 seconds of infamy."
UC's basketball program had past image issues with off-court incidents involving players and the 2004 drunken-driving arrest of coach Bob Huggins that culminated in Huggins' ouster. Xavier has largely avoided negative publicity while building its basketball program into a national power.
"We are not the only ones something like this has happened to, but it was definitely a new experience for Xavier," said Paul Ruppe, a 1992 Xavier graduate who gathered with some 60 other alumni in Chicago to watch the game on TV. "For the image we try to maintain and uphold, it was disappointing, let's put it that way."
"It doesn't make Xavier look very good, and it doesn't make UC look very good. It's kind of ridiculous, honestly," said Brandon Henson, a Bearcat fan. "I guess Xavier fans used to say UC recruits these kinds of players; guess what, Xavier does, too."
UC president Gregory Williams said in a statement: "We hold our student-athletes to a high standard and this behavior will not be tolerated."
Xavier said that the "unsportsmanlike events" Saturday don't reflect the Jesuit Catholic school's value and traditions, and it pledged to work to "make things right." The statement said University president Michael Graham has been in touch with Williams to discuss how the schools can work together to promote cooperation and sportsmanship.
AP Sports Writer Joe Kay contributed to this report.