NCAA officials were at Louisville on Monday and Tuesday, interviewing members of the Cardinals basketball program concerning recent allegations made by former escort Katina Powell, multiple sources told ESPN's Jeff Goodman.
Louisville spokesman Kenny Klein said he "can't comment on any matter concerning the NCAA investigation."
In a letter to students, Louisville president James Ramsey said the school is also reviewing the allegations and see the charges as "not an isolated athletic issue" but rather something that affects the entire university community.
Powell, in her book, "Breaking Cardinal Rules: Basketball and the Escort Queen," alleged that former Cardinals assistant Andre McGee hired her and other dancers for sex parties at the players' dormitory.
Powell contends that she helped organize nearly two dozen on-campus parties involving strippers and sex with escorts. The parties, she says, were mainly designed to lure high school basketball recruits to sign with the school.
Louisville coach Rick Pitino has denied knowledge of the activities detailed in Powell's book.
The allegations have prompted four separate investigations, including one by the NCAA. The Louisville campus police announced Oct. 6 they are working with the Louisville Metro Police to review the allegations for possible criminal charges.
McGee, on Friday, resigned as assistant coach at the University of Missouri-Kansas City, saying he could no longer do his job as he fights "false allegations" against him.
Powell is disinclined to help in any of the ongoing investigations unless she is able to receive immunity, her attorney Larry Wilder said Tuesday.