LOS ANGELES – New revelations from a Los Angeles civil lawsuit show school officials knew of convicted pedophile teacher Mark Berndt’s sexual depravity three decades before he was busted for lewd acts with students.

The former Miramonte Elementary School teacher was sentenced to 25 years in prison last November, but civil cases brought by his victims against the Los Angeles Unified School District. Last year, 63 children and their families settled a lawsuit for $30 million, but a second civil suit involving 70 more plaintiffs continues to unravel Berndt’s disturbing history, the Huffington Post reports.

“In May, Los Angeles Judge John Shepard Wiley said that Berndt may have abused as many as 100 children, citing a 512-page investigative report from the local Sheriff’s Department,” according to the news site.

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“Investigators found that Berndt molested his students, getting them to touch him inappropriately and exposing himself to them by sitting in shorts without underwear,” although Berndt’s attorney denies the molestation allegations, the Huffington Post reports.

A drug store technician initially exposed the third grade teacher’s misdeeds while exposing pictures of blindfolded children with spoonfuls of semen held to their face. Other pictures showed students with cockroaches crawling on them, the news site reports.

Investigators believed Berndt’s disgusting actions stretched back to the 1990s, but documents in the newest civil lawsuit show school officials became aware of his bizarre behavior as early as 1983, according to the Los Angeles Times.

“In 1983, a South Los Angeles elementary school principal received a call about one of his teachers, a 32-year-old just a few years on the job. One a student field trip to a museum, Mark Berndt had dropped his pants, a parent complained,” The Los Angeles Times reports.

“The principal called the parent back and jotted notes about the incident in a memo. Berndt remained at the school.

“’Thanks again for the support you gave me,’ Berndt said in a handwritten note to the principal shortly after the complaint. ‘I did learn at least one thing for sure! Not to take students to the museum while wearing baggy shorts!’”

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There were more complaints from students, parents, and co-working in the 1990s, the Times reports.

In one incident, several fourth-grade girls complained to the principal that Berndt masturbated in class, but the principal accused the students of lying. In another incident, Berndt wore loose-fitting shorts that exposed his genitals, which prompted a young teacher who was observing the class to report the inappropriate attire to school officials.

“’I know, baby. I’ve had several complaints for parents, too, but there’s nothing we can do about it,’ the teacher recalled the principal saying,” the Times reports. The principal, of course, denies the conversation ever took place.

District officials have blamed the problems and lack of action on the district’s loose record keeping, which often resulted in lost files or lost complaints, according to the LA Times.

“… (S)ometimes site files get discarded when principals change,” George McKenna, a former administrator who was recently elected to the school board, told the news site. “Some principals keep the file. Some principals take them with them when they leave. They shouldn’t, but some of them have done that.”

LA district officials have refused to discuss the complaints against Berndt “out of respect for the students and families involved,” district spokesman Sean Rossall told the Times.