Newport Beach resident Robert Pimentel, 57, was arrested Wednesday. He taught at George De La Torre Jr. Elementary School in Wilmington.
An investigation by the Los Angeles Police Department began last March after several girls told their parents they had been inappropriately touched by a 4th-grade teacher. The LAPD's investigation revealed a total of 21 victims, including 20 children and one adult victim.
The Los Angeles County District Attorney's Office has filed eight counts of continuous sexual abuse and seven counts of lewd acts upon a child against Pimental. He was held on $12 million bond.
The LAPD says it took time to build the case against Pimental.
"Due to the number of victims involved in this case, that's what took so long for it to culminate," said Det. Gus Villanueva with the LAPD.
Laney Gonzalez, 13, a former student at the school, wasn't one of Pimental's students, but she said she thought his behavior was odd.
"During lunchtime, he would have most of the girls in his classroom, playing songs for them and talking to them," said Gonzalez. "He would hug most of my friends."
Pimentel was removed from the classroom on March 16, 2012, a day after the investigation was launched. The LAUSD said dismissal proceedings were initiated, but Pimentel chose to retire. He was employed with the district since 1974.
United Teachers Los Angeles issued a statement Wednesday night:
"UTLA is not familiar with the details of this case. We do know the individual resigned and that he is no longer a member of UTLA. The union will not be involved in his defense. The allegations described are horrific. As teachers we have a duty to uphold the trust our students and their parents place in us. We urge our members and the community to cooperate with ongoing law enforcement investigations in this case."
This is the latest in a string of teacher arrests in the LAUSD for alleged sexual misconduct. Mark Berndt, a former teacher at Miramonte Elementary School, was arrested in January 2012 and charged with 23 counts of lewd conduct.