On the morning of 5 June, the Israeli Air Force struck Egyptian air fields, destroying much of the Egyptian Air Force. Before the day ended, Israeli armored units had cut through Egyptian defense lines and captured the town of el-Arish. The next day, Amer ordered the immediate withdrawal of Egyptian troops from Sinai—causing the majority of Egyptian casualties during the war. Israel quickly captured Sinai and the Gaza Strip from Egypt, the West Bank from Jordan, and the Golan Heights from Syria.