A longtime elementary school teacher in Los Angeles stands accused of abusing students for years.
It took months for the sheriff and district attorney to finish their investigation and finally tell the public, and there are now charges of a major cover-up.
At Miramonte Elementary School in South Los Angeles, parents were incensed they hadn't heard until now of a year-long investigation of third-grade teacher Mark Berndt. The popular teacher, at the school for 30 years, has been charged with lewd acts with 23 students.
Debra Harmon, the mother of a first grader, said, "It is an outrage for something like this to go on in our school undetected."
Berndt's alleged crimes involved girls and boys between the ages of seven and 10 -- and happened in his classroom. It might never have come to light were it not for an employee at a local photography shop.
The film processor grew concerned and alerted authorities to Berndt's photos -- 290 of them -- of children blindfolded, scotch tape over their mouths.
Sgt. Dan Scott, of the Los Angeles County Sheriff's Department, said, "To an average person looking at these pictures, seeing the children smiling, they would have probably thought, maybe they're playing a game, but to a trained detective in child abuse cases, they felt a gut feeling there was more."
When they searched Berndt's classroom, investigators found DNA evidence that linked Berndt him to sexual crimes against at least 23 children. School officials immediately removed him from the classroom back in March. He was put under surveillance to keep him from children as police built their case.
Kimberly Kirklan, a mother of three daughters, said, "You don't know what kind of diseases this man has. You don't know any history about this man. And you're taking our innocent babies and you're basically tainting them."
Berndt's bail has been raised to $23 million and his arraignment, set for Wednesday, has been put off. If convicted, he faces a possible sentence of life in prison.
To watch Whitaker's full report, click on the video in the player above.
On "CBS This Morning," CBS News' John Miller, a former Los Angeles Police Department official, talked about the case, including what some parents of school children in this case knew that others didn't, how many cases of child pornography are discovered and what states require reporting of potential child abuse. For that discussion click on the video in the player below.