Why was egypt’s former president imprisoned after he resigned from office?

It was President Hosni Mubarak.  He became president of Egypt on October 11, 1981 after the assassination of President Anwar Sadat.  His ruled Egypt for almost 30 years.  His administration was criticized for various crimes such as corruption and human rights abuse.  This eventually led to a mass protest against his regime.  Despite the promise of constitutional reforms, it was not accepted by the people and Mubarak resigned and escaped only to be placed under house arrest. He was ordered to stand Trial on May 25, 2011 and found guilty of sabotaging the economy on May 28, 2011 by an administrative court in Cairo and was ordered to pay with his assets.  He would later be tried for other crimes where some he was convicted while others were dismissed.