Pennsylvania prosecutors are considering criminal charges against former top Penn State University officials for allegedly concealing what they knew about the conduct of former assistant football coach Jerry Sandusky, law enforcement sources said Monday.

NBC News reported the story as Sandusky's trial began Monday on 52 counts alleging that he abused 10 boys over 15 years.

The sources said investigators had obtained new evidence, including internal university email messages and other documents.

Prosecutors made their first public reference to the material in a court filing Monday, saying they included a file on Sandusky that was “created, maintained and possessed” by former Penn State Vice President Gary Schultz.

The prosecutors also said the recently discovered emails “contradict” the testimony of Schultz, former athletic director Tim Curley “and others” before a grand jury about what they knew about an allegation of possible sexual misconduct by Sandusky.

A spokeswoman for Curley and Schultz said their lawyers had not yet seen the new filing by prosecutors and couldn’t comment on it. Both men were charged with perjury for their testimony regarding Sandusky last November.

Legal sources tell NBC the emails and documents were recently discovered by investigators for former FBI director Louis Freeh, whose firm has been hired by Penn State to conduct an internal investigation into the school’s handling of the Sandusky matter.

Meanwhile, the first witness called in the trial testified Monday that Sandusky treated him like his girlfriend when he was a young teenager, showering together and engaging in oral sex, Reuters reported.

The graphic testimony by the man now 28 -- one of eight alleged victims of Sandusky due to be prosecution witnesses -- came after jurors heard opening statements from prosecutors and the defense.