The retrial of ousted Egyptian president Hosni Mubarak and his two sons on charges of corruption will open on April 4, a judicial official said on Monday. In January, the Court of Cassation overturned Mubarak's conviction on corruption charges and ordered that he and his sons Alaa and Gamal be tried again. A lower court had sentenced Mubarak to three years and his sons to four years for allegedly embezzling 16 million dollars (14 million euros) earmarked for the maintenance of presidential palaces.