 Throughout the night of October 21 / 22, the large artillery forces the Egyptians had concentrated began harassing the Israelis. The Egyptians had identified command posts and tank concentration areas for attack, especially at Serabaeum and Ain Ghasin, as well likely routes of attack, and continued to provide a withering fire support during the Israeli attack. At morning, Israeli aircraft attacked Egyptian positions, concentrating on Jebel Mariam, Abu 'Atwa, Nefisha, and al-Galaa' base, and at noon they destroyed the Abu Gamoos Bridge at Ismailia. At this time, company-sized units of armor and infantry advanced against the Upper Bridge and the bridges at Nefisha but were repelled by Sagger missiles.
