Delaware Attorney General Beau Biden said the attacks cited in the indictment were discovered through video recordings made by Dr. Earl B. Bradley, The Wilmington News Journal reported Tuesday.
Bradley allegedly forced the victims, all named Jane Doe or John Doe in the indictment, to engage in sexual acts including intercourse and oral sex, the newspaper reported.
State police and the FBI analyzed videotapes, computer hard drives and digital files taken from Bradley's home and office, Biden said.
Experts say the case against Bradley could be the worst child sexual abuse by a pediatrician in American history.
Biden said it was "unique" in Delaware history. Nationally, he said, "I know of no other (case) that has this many victims."
"These were crimes committed against the most vulnerable among us, those without voices," Biden said. "They were committed by someone in whom the community and parents had placed their trust."