The cigar-chomping Mr. Savile, who died in 2011 at the age of 84, was one of the most celebrated and beloved personalities in Britain until accusations came to light in 2012 that he had preyed on scores of children and adults. The disclosure shocked Britain and the BBC.

“He used his celebrity status, his entree to the BBC and his connections with other stars as bait with which to draw young girls into his sphere,” the report said, calling Mr. Savile a pedophile who had sexually abused young children.

A separate report by Dame Janet also issued on Thursday on the conduct of another former broadcaster, Stuart Hall, found that he had abused 21 female victims and that members of BBC management had known about his behavior.

Mr. Hall, 86, was imprisoned in 2013 for indecently assaulting 13 girls from 1967 to 1985. The report told how he had cut the pubic hair of one of his victims, a girl of 14 or 15, and put the clippings in a picture frame on his shelf at BBC premises.

Tony Hall, the director general of the BBC, who is no relation to Stuart Hall, apologized to the victims. “A serial rapist and a predatory sexual abuser both hid in plain sight for decades,” he said in a statement published by the broadcaster. “It was a dark chapter in the history of the organization, but a much darker one for all of you. The BBC failed you when it should have protected you. I am deeply sorry for the hurt caused to each and every one of you.”

On Thursday, Tony Hall said that a D.J., Tony Blackburn, had “parted company” with the BBC after failing to cooperate fully with the Savile inquiry. According to the BBC, Mr. Blackburn said the report had accused him of being among celebrities who had seduced a 15-year-old girl, which he has denied. Citing the director general, the BBC said the inquiry had rejected Mr. Blackburn’s evidence.