A former pediatric doctor Massachusetts reached a plea deal with federal prosecutors in a child pornography case, the Huffington Post reported.

Richard Keller, 57, is the former medical director of Phillips Academy, a prestigious boarding school in Massachusetts. Keller also worked at the Children's Hospital of Boston as a pediatric endocrinologist and taught at Harvard Medical School. 

He pleaded not guilty last year to charges of possessing and receiving child pornography. 

Prosecutors and Keller's lawyer filed a court report this way saying they reached a plea deal in the case. They also asked to schedule a change-of-plea hearing next month, giving them time to complete details of the agreement. 

Max Stern, the former doctor's lawyer, and a spokeswoman for U.S. Attorney Carmen Ortiz both declined to comment on whether Keller will plead guilty to all three charges against him or if a joint sentencing will be suggested to the judge. 

If convicted, Keller faces up to 20 years in prison -- including a five-year mandatory minimum for receiving child pornography. He is charged with obtaining pictures and videos of boys aged 7 to 16 engaging in sexually explicit behavior. 

Keller resigned from Phillips Academy following the allegations and the school said they will not renew his contract. John Palfrey, head of the school, sent an email notifying students and parents that their medical director was being fired due to professional misconduct unrelated to the federal charges against him. 

He also gave up his state medical license after his arrest last September.

According to investigators, Keller's name popped up during their search of an unidentified foreign company suspected of producing child pornography. They reportedly discovered orders made by Keller directed to two addresses -- a rented post office box and the student health center at the boarding school. 

Officials also found child pornography in his house, including over 500 printouts and DVDs.