Kentucky police used pepper spray and an armored car to calm disturbances that erupted at the tail end of celebrations following the Cardinals' NCAA championship win over Michigan.
Gatherings were mostly peaceful Monday night following Louisville's 82-76 victory - the school's first title since 1986. Louisville police said most of the 23 arrests were due to drunken or disorderly conduct.
But things got out of hand as the celebration was winding down early Tuesday, with police in riot gear and an armored car arriving after the crowds refused to disperse.
Police spokeswoman Carey Klain says several scuffles followed. Some partiers threw bottles at police, hitting an officer in the head. Police responded with pepper spray.
Klain says the officer received minor injuries and was treated at a hospital and released.