The official says that today's transfer of toppled President Mohammed Morsi came 10 days after he was placed temporarily in a hospital room at Borg al-Arab prison, near the Mediterranean city of Alexandria.
The official spoke on condition of anonymity because he was not authorised to speak to the press.
Morsi arrived at the prison on November 4, the day of his first court appearance on charges of inciting violence and murder in connection to the killing of protesters outside of the presidential palace in December.