LOS ANGELES (AP) — The University of Southern California is challenging the fundraising reputation of a once-lauded medical school dean who resigned and faces allegations that he used drugs and hobnobbed with criminals.

Dr. Carmen A. Puliafito said he raised $1 billion for the Keck School of Medicine.

That assertion was challenged Friday in a school letter to "Friends of USC" from Senior Vice President Albert R. Checcio that laid out results of a USC fundraising campaign.

"Let me state the facts," Checcio wrote. "In the past seven years, Dr. Puliafito was responsible for barely one percent of the more than $1.2 billion that USC raised for medicine."

He added later: "No single individual is ever responsible for — or can take sole credit for — raising the money."

Puliafito, 66, is a renowned eye surgeon. He led the Keck School of Medicine for nearly a decade and was praised for raising funds and attracting talent.

He resigned in March 2016, saying he wanted to explore outside opportunities but remained on the faculty and represented USC at public events.

Last month, USC announced it would fire Puliafito and strip him of tenure after the Los Angeles Times reported that he kept company with a circle of criminals and drug users. The newspaper said it had videos of the dean apparently smoking methamphetamine and taking Ecstasy. Citing a police report, it also reported that Puliafito was present when a woman overdosed in a Pasadena hotel room only weeks before he resigned.

USC has hired a former federal prosecutor to investigate.

The Associated Press was unable to find a working telephone number on Friday for Puliafito, who has never commented publicly on the accusations.