Some of the incidents involved in the ombudsman’s investigation are believed to have taken place in police custody suites, the Nolan Show understands.
Earlier, Police Ombudsman Hugh Hume said in a statement that the investigation has identified “multiple potential victims together with a substantial number of witnesses”.
The PSNI said it “welcomes and will fully co-operate with the investigation”.
McAllister told the Nolan Show that when she first became aware of the accused’s arrest last year, her “understanding was that is was going to be absolutely huge, in terms of the level of work that was going to be required of the ombudsman, and the number of victims”.
Sinn Féin Mid Ulster MLA Linda Dillon also commented on the number of alleged incidents.
“Since we’re hearing that there are potentially over a hundred incidents in relation to this case, I’m glad to hear that the police ombudsman’s office is going to put immense resources into investigating this,” she said.