The Los Angeles school district said it is investigating to learn how a teacher suspected of lewd conduct against his students eluded suspicion for so long. The district\'s internal investigation came as police detectives said several new potential victims stepped forward and parents of students at Miramonte Elementary School demanded to know why the alleged crimes went undetected for five years, the Los Angeles Times reported Thursday. Former elementary school teacher Mark Berndt, 61, has been charged with 23 counts of committing lewd acts on children. Prosecutors alleged he took hundreds of photos of the children, many with a milky substance around their mouths. The charges date to 2005, prosecutors said. Berndt has not entered a plea and was jailed on $23 million bail. Police said they learned of the misconduct in late 2010 when Berndt allegedly took photos to be developed at drug store, where photo technician saw the images then called police. When Los Angeles County Sheriff\'s Department detectives showed school officials the photos in January 2011, and the district suspended Berndt and later fired him. \"How do I make sense out of the fact that this took place over a number of years and no one seemed to know about that?\" Los Angeles Unified School District Superintendent John Deasy told the Times Wednesday. \"I\'m definitely trying to understand how someone could not have known.\" Deasy and other school officials said they don\'t have records of complaints about Berndt, who is accused of spoon-feeding blindfolded students his semen as part of a \"tasting game,\" among other things. However, one woman who said she was a former student told the Times Wednesday school officials looked into a complaint made against Berndt during the 1990-91 school year. Marlene Trujillo said she was a fourth-grader in his class at the time, and was called to the school guidance counselor\'s office along with two other girls who complained about Berndt. She told the Times the counselor \"just told us it\'s not very good to make stories up. She said it was our imagination. It was never talked about again.\" Trujillo said she remembered Berndt as a good teacher.