strayed into Israeli airspace and was suspected to be on a terrorist mission when it did not respond. The plane was shot down by the Israeli Air Force over the Sinai Peninsula under direct orders from Elazar, killing over 100 civilians. Only later was it discovered that this was a civilian aircraft that had made a navigational error. On 27 May 1973, the IDF announced a state of emergency and reserve troops were called up in response to a movement of Egyptian troops. The state of emergency was cancelled when it became clear that this was only an exercise. This event had a major impact on the General Staff, as it led them to believe that the Egyptian forces were not preparing for war, later that year, on Yom Kippur. After the war however, it became apparent that these frequent maneuvers carried out by the Egyptians were part of an elaborate ruse meant to induce complacency in the Israelis regarding the true intentions of Egyptian troop movements at the time the actual attack took place. On 13 September, Israel shot down thirteen Syrian fighter jets, which had attempted to down Israeli aircraft. The Yom Kippur War Events leading up to the war In 1957, Israel was forced, under American pressure, to withdraw from the Sinai which it had occupied since attacking Egypt the previous year. Closing the Tiran strait to Israeli ships by Egyptian President Gamal Abdel Nasser in 1967 was one of the major causes for the 1967 war, during which Israel re-occupied the Sinai peninsula. On 1 October 1973, the armies of Egypt and Syria were placed on alert. Due to an erroneous intelligence assessment and poor decisions by the Israeli military, the IDF responded with only limited measures, few reserve units were called up, and it was determined that war was "unlikely." In the early hours of 6 October (on Yom Kippur, the holiest of the Jewish holidays), Elazar finally became convinced that war would indeed break out that same day, even though the Chief of Military Intelligence Major General Eli Zeira and the Minister of Defense Moshe Dayan still believed that this was highly unlikely. Dayan's conviction had two major consequences: Dayan refused to approve Elazar's request for a general call-up of the reserves (Elazar nevertheless eventually decided independently on a limited call-up, beginning on 5 October). Dayan refused to approve Elazar's recommendation that the IDF