LANSING, Mich.— State Attorney General Dana Nessel has suspended a nearly two-year-long investigation into Michigan State University's handling of complaints against now-imprisoned serial sexual abuser Larry Nassar, a spokeswoman said Tuesday.

The probe, which began under Nessel's predecessor, has resulted in charges against three former school officials. One was convicted. Two others, including former president Lou Anna Simon, were ordered to trial. Their cases will continue to be prosecuted.

It is unclear if or when the investigation will resume. Investigators want the university to waive attorney-client privilege on more than 6,000 documents, and they hope to interview former interim president John Engler, who took over following Simon's resignation, Nessel spokeswoman Kelly Rossman-McKinney said.

The school's governing board infuriated Nassar victims this year after dropping a promised independent review of sex assaults committed by Nassar, a former campus sports physician who also worked for USA Gymnastics, which trains Olympians.

The trustees deadlocked over releasing the documents, though many now are personally reviewing them. Some said releasing privileged information would jeopardize the university's lawsuit against insurers to help cover a $500 million payout to hundreds of victims and related legal costs.

Earlier this year, Engler's lawyer and an attorney in Nessel's office were at odds over his availability to speak with investigators. The attorney general's office had wanted to talk to Engler about campus changes after the sex-assault scandal involving Nassar, who molested athletes under the guise of treatment. Engler was interim president for about a year until resigning amid fallout over remarks he made about some victims.

“We appreciate all the time and hard work the Attorney General’s office has put into their investigation over the past two years,” university spokeswoman Emily Gerkin Guerrant said in a statement Tuesday. “MSU has cooperated fully with the inquiry, including handing over all facts associated with the case."

She said the school has been investigated and reviewed by more than a dozen other entities and governments.

“We continue making improvements and increasing our education and prevention efforts to make sure this can never happen again," Gerkin Guerrant said. “Our hearts are with the survivors and their families as they continue their healing as well."

In February, Nessel said a judge had reviewed the privileged documents and it did not appear her office would be getting any additional documents. As recently as last week, Rachael Denhollander — a former gymnast and Nassar victim — said the documents may contain factual information and urged Michigan State to release the documents “now.”

While the MSU probe has been paused, Nessel's investigation continues into unspecified complaints against former U.S. Olympic women's gymnastics team coach John Geddert. He owned and operated Twistars, a Lansing-area gym where Nassar offered treatments.

During Nassar's 2018 sentencings, some victims complained that Geddert was physically abusive and indifferent to injuries, and forced them to see Nassar. He has insisted that he had "zero knowledge" of Nassar's crimes.