The vanguard arrived before Alexandria on 9 July 919, while the main body under al-Qa'im, came in September/October. The arrival of the Fatimid expeditionary force in July 919 caught the city's governor, Dhuka's son Muzaffar, by surprise. Along with his aides and many of the populace, he fled without giving battle.[5][7] Having already once acknowledged Fatimid sovereignty and hence now considered in revolt, the city was sacked by the Fatimid troops.[5]