ANN ARBOR, Mich. -- Michigan athletic director Warde Manuel said police are investigating what coach Jim Harbaugh called an assault on two of his players in the tunnel after Michigan's 29-7 win over Michigan State on Saturday.
Video on social media from the Detroit News showed Michigan State players gathered around Michigan defensive back Ja'Den McBurrows throwing punches and kicks.
What happened after the game is completely unacceptable. I've talked to the commissioner, he's looking into it," Manuel said. "The police are also looking into it, because they've seen the video and they're addressing it. We will leave it in their hands, but this is not how we should interact after a game.
"This is not the way another team should grab a player and do what they did, it's completely and utterly unacceptable. We will let the Big Ten and law enforcement handle it, but this is not what a rivalry should be about."
Harbaugh said two players were assaulted and said one player has a potential nose injury, but had not been diagnosed.
Harbaugh was visibly distraught about the incident and said instead of celebrating in the locker room, the coaches were addressing the incident after the game.
"Just like anybody, you want to protect your players," Harbaugh said. "Ten on one, whatever it was, it was just bad. It needs to be investigated and brought to a conclusion. Our athletic director will make sure that that takes place."
Hours after the game, a joint statement was released.
"The University of Michigan Police, in partnership with Michigan State University Police, Michigan Athletics and Michigan football, is actively reviewing footage and investigating the postgame incident," the statement said. "Situations like these, and the safety of the community, are taken very seriously."
Michigan players Blake Corum, J.J. McCarthy, Jake Moody and Junior Colson spoke after the game, as well, but none had seen the video or the incident in real time and had no comment.
Michigan State coach Mel Tucker initially said after the game that he didn't know what happened, but tweeted Sunday morning that "there is no excuse for behavior that puts our team or our opponents at risk."
Michigan State president Samuel L. Stanley Jr. said in a statement that he is "extremely saddened" by the Spartan players' "unacceptable behavior" and that the players would be held responsible.
"I'm extremely saddened by this incident and the unacceptable behavior depicted by members of our football program," Stanley said in the statement released Sunday morning from the school. "On behalf of Michigan State University, my heartfelt apology to the University of Michigan and the student athletes who were injured.
"There is no provocation that could justify the behavior we are seeing on the videos. Rivalries can be intense but should never be violent.
"Coach Tucker will be holding the players involved responsible, and our football team and university will be cooperating with all related investigations by law enforcement and the Big Ten Conference."
University of Michigan president Santa Ono said in a statement that Stanley personally apologized for the incident.
"I have spoken with Michigan State President Samuel Stanley and he personally apologized for last night's incident in the Michigan Stadium tunnel," Ono said. "We are in strong agreement that this behavior is unacceptable.
"The safety of our students will always come first. Both universities are cooperating fully with Big Ten and law enforcement investigations. I appreciate the outreach from President Stanley and others from the MSU community. Both institutions are committed to taking all necessary steps to ensure that such a situation does not occur again in the future."
The Big Ten said in a statement that it "is aware" of the incident and "is currently gathering information, will thoroughly review the facts, and will take appropriate action."