MADISON, Wis. (AP) -- The University of Wisconsin-Madison says a third allegation of misconduct has surfaced against a former top athletic official.

Chancellor David Ward said in a statement Thursday that university police are investigating a new allegation involving John Chadima (CHAD'-ih-muh). Ward says the UW Police Department believes the allegation is credible.

Ward is calling for other potential victims to come forward, a tactic that Chadima's lawyer calls a "reckless campaign of character assassination." Attorney Charles Giesen says Chadima is being smeared by anonymous allegations without a meaningful opportunity to respond.

Chadima resigned after he was accused of sexually assaulting a male student at a Rose Bowl party. Ward says the latest allegation involves Chadima and an adult male.

Online court records do not show that Chadima faces any criminal charges.