The Sack of Damietta was a successful raid on the port city of Damietta on the Nile Delta by the Byzantine navy on 22–24 May 853. The city, whose garrison was absent at the time, was sacked and plundered, yielding not only many captives but also large quantities of weapons and supplies intended for the Emirate of Crete. The Byzantine attack, which was repeated in the subsequent years, shocked the Abbasid authorities, and urgent measures were taken to refortify the coasts and strengthen the local fleet, beginning a revival of the Egyptian navy that culminated in the Tulunid and Fatimid periods.