As early as July 1, 1967, Egypt began shelling Israeli positions near the Suez Canal. On October 21, 1967, Egypt sank the Israeli destroyer Eilat, killing 47. Less than a year later, Egyptian artillery began to shell Israeli positions along the Suez Canal.
Nasser believed that because most of Israel's army consisted of reserves, it could not withstand a lengthy war of attrition. He believed Israel would be unable to endure the economic burden, and the constant casualties would undermine Israeli morale.
The bloody War of Attrition lasted roughly three years. Israel lost 15 combat aircraft, most shot down by antiaircraft guns and missiles. The Israeli death toll between June 15, 1967, and August 8, 1970, was 1,424 soldiers and more than 100 civilians. Another 2,000 soldiers and 700 civilians were wounded.
Sources: Israeli Foreign Ministry