In 1981, Al-Zawahiri was one of hundreds arrested following the assassination of President Anwar Sadat. Initially, the plan was derailed when authorities were alerted to Al-Jihad's plan by the arrest of an operative carrying crucial information, in February 1981. President Sadat ordered the roundup of more than 1500 people, including many Al-Jihad members, but missed a cell in the military led by Lieutenant Khalid Islambouli, who succeeded in assassinating Sadat during a military parade that October. His lawyer, Montasser el-Zayat, said that Zawahiri was tortured in prison.