In a message to BBC staff, Director General George Enwistle has said he is "appalled" by the things he saw in the ITV Jimmy Savile documentary.
In the email, obtained by The Guardian, Mr Enwistle also encourages those who may have information that may help the BBC's investigation team to come forward.
Jimmy Savile was questioned as a suspect by police investigating the Yorkshire Ripper, according to a retired police officer.
Jimmy Savile's nephew has spoken of the emotional turmoil his family is going through in the wake of the sex abuse allegations.
A colleague of Jimmy Savile allegedly raped a woman on BBC premises in 1970, ITV News has been told.