By Victor Skinner

LOS ANGELES – A Los Angeles elementary teacher faces numerous felony and misdemeanor charges after he allegedly molested 20 students during his 40-year career in the school district.

Authorities say a 10-month investigation revealed Robert Pimentel of Newport Beach repeatedly molested female students at George De La Torre Jr. Elementary School, where he taught fourth grade, the Associated Press reports.

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Pimentel, 57, was charged Wednesday with eight felonies of continual sexual abuse and seven felonies for lewd acts upon a child. He has not been arraigned, but his bail is set at $12 million.

“Police and school officials also said Pimentel is suspected of the sexual abuse of one adult, but did not say what role if any that person had at the school,” according to the AP.

The news agency reports Pimentel left his position last March when several students told their parents he touched them inappropriately at school.

School officials removed Pimentel from the school, and notified parents and authorities, but the long-time teacher retired from the district before the school board could initiate the termination process, the AP reports.

LAUSD Superintendent John Deasy told the AP the district also removed the principal at De La Torre Elementary because of the way the incident was handled, but didn’t provide specifics.

Court records and school officials said Pimentel is accused of touching young girls under and on top of their clothing between Sept. 2011 and March 2012. Pimentel’s teachers union issued a statement describing the incident as “horrific,” and said it would not be involved in his defense, according to the AP.

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Pimentel’s charges come on the heels of several other child molestation cases in the Los Angeles district in recent years. Hundreds of parents and students currently have pending litigation against the district stemming from another elementary teacher – Mark Berndt – who was arrested last year for 23 counts of lewd conduct.

Last month, a jury found the LA district liable for the repeated sexual abuse of a 10-year-old student by another teacher, and ordered the district to pay $6.9 million in damages.