The University of Southern California's embattled president stepped down Tuesday in the wake of a sex-abuse scandal that has led to hundreds of plaintiffs suing the university and a former gynecologist. Trustees have appointed an acting president.

C.L. Max Nikias, 65, and school administrators faced mounting criticism for ignoring decades of sexual misconduct complaints against Dr. George Tyndall, who worked at the university clinic for 30 years.

Nikias agreed in May to step down at an unspecified date, Fox News previously reported. But faculty members addressed a petition to the trustees last week, indicating they had waited long enough for Nikias to leave.

Tyndall, who has since retired, is the focus of some two-dozen lawsuits and a police investigation into allegations involving at least 50 women.

The lawsuits allege Tyndall routinely made crude comments, took inappropriate photos and forced plaintiffs to strip naked and groped them under the guise of medical treatment.

More than 300 people are also now suing USC over its alleged failure to prevent sexual abuse by Tyndall.

Nikias agreed to relinquish his role, but becomes president emeritus and a life trustee of the school, Board of Trustees Chair Rick J. Caruso wrote in a letter to students, faculty and alumni.

“As he has always done, Max is taking this action in what he believes to be in the best interest of the university following controversies that have arisen from the unfortunate and unacceptable acts of others," Carusa wrote, according to USC News. "From our investigations, which are not yet completed, we have found absolutely no wrongdoing on Max’s part.”

"As he has always done, Max is taking this action in what he believes to be in the best interest of the university following controversies that have arisen from the unfortunate and unacceptable acts of others." — Rick J. Caruso, chairman, USC board of trustees

Wanda M. Austin, who is a board member, was appointed interim president.

"She is a professional of impeccable integrity and character," Caruso wrote, according to the Los Angeles Times. "She is deeply committed to USC, and I know that she plans to devote time in the coming weeks to listen to the views of faculty, staff, students, and our broader community on what is needed to successfully move us into our next chapter."

Austin holds a USC engineering degree and was president and CEO of her own company, the Aerospace Corp. She is a former member of the President's Council of Advisers on Science and Technology and currently serves on the boards of Chevron and Amgen, according to Caruso.

She is "a strong advocate for science, technology, engineering, and math (STEM) disciplines as well as for minorities and women," Caruso wrote.

Meanwhile, a search for a permanent replacement for Nikias is underway, the Times reported.

“Our goal is to complete this search within four to six months,” Caruso wrote in the letter, according to the Times.

NEW USC LEADER PROMISES 'THOROUGH AND INDEPENDENT' PROBE OF GYNECOLOGIST SEX SCANDAL

In his letter, Caruso promised reforms."As I have said previously, it is evident that the recent crises have resulted from systemic and cultural failures," he wrote.

"Both the behavior and the environment that allowed it to persist are inexcusable and will no longer be tolerated."

He also noted that the school has a newly formed Office for Professional Ethics to monitor and investigate complaints.

"Both the behavior and the environment that allowed it to persist are inexcusable and will no longer be tolerated." — Rick Caruso, Board of Trustees Chair

The Associated Press contributed to this report.