On 6 October 1981, Sadat was assassinated during the annual victory parade held in Cairo to celebrate Egypt's crossing of the Suez Canal. Islambouli emptied his assault rifle into Sadat's body while in the front of the grandstand, mortally wounding the President. In addition to Sadat, eleven others were killed, including the Cuban ambassador, an Omani general, a Coptic Orthodox bishop and Samir Helmy, the head of Egypt's Central Auditing Agency (CAA). Twenty-eight were wounded, including Vice President Hosni Mubarak, Irish Defence Minister James Tully, and four US military liaison officers. The assassination squad was led by Lieutenant Khalid Islambouli after a fatwā approving the assassination had been obtained from Omar Abdel-Rahman. Islambouli was tried, found guilty, sentenced to death, and executed by firing squad in April 1982. Sadat was succeeded by his vice president Hosni Mubarak, whose hand was injured during the attack. Sadat's funeral was attended by a record number of dignitaries from around the world, including a rare simultaneous attendance by three former US presidents: Gerald Ford, Jimmy Carter and Richard Nixon. Sudan's President Gaafar Nimeiry was the only Arab head of state to attend the funeral. Only 3 of 24 states in the Arab League—Oman, Somalia and Sudan—sent representatives at all. Israel's prime minister, Menachem Begin, considered Sadat a personal friend and insisted on attending the funeral, walking throughout the funeral procession so as not to desecrate the Sabbath. Sadat was buried in the unknown soldier memorial in Cairo, across the street from the stand where he was assassinated. Over three hundred Islamic radicals were indicted in the trial of assassin Khalid Islambouli, including future al-Qaeda leader Ayman al-Zawahiri, Omar Abdel-Rahman, and Abd al-Hamid Kishk. The trial was covered by the international press and Zawahiri's knowledge of English made him the de facto spokesman for the defendants. Zawahiri was released from prison in 1984. Abboud al-Zomor and Tareq al-Zomor, two Islamic Jihad leaders imprisoned in connection with the assassination, were released on 11 March 2011. Despite these facts, the nephew of the late president, Talaat Sadat, claimed that the assassination was an international conspiracy. On 31 October 2006, he was sentenced to a year in prison for defaming Egypt's armed forces, less than a month after he gave the interview accusing Egyptian generals of masterminding his uncle's assassination.