Amru, on taking possession of the city, found it nearly abandoned; he prohibited his troops from plundering, and, leaving a small garrison to guard the place, hastened with his main army in pursuit of the fugitive Greeks.  In the mean time the ships, which had taken off a part of the garrison, were still lingering on the coast, and tidings reached them that the Moslem general had departed and had left the captured city nearly defenceless.  They immediately made sail back for Alexandria, and entered the port in the night.  The Greek soldiers surprised the sentinels, got possession of the city, and put most of the Moslems they found there to the sword.

Amru was in full pursuit of the Greek fugitives when he heard of the recapture of the city.  Mortified at his own negligence in leaving so rich a conquest with so slight a guard, he returned in all haste, resolved to retake it by storm.  The Greeks, however, had fortified themselves strongly in the castle and made stout resistance.  Amru was obliged, therefore, to besiege it a second time, but the siege was short.  The castle was carried by assault; many of the Greeks were cut to pieces, the rest escaped once more to their ships and now gave up the capital as lost.  All this occurred in the nineteenth year of the Hegira, and the year 640 of the Christian era.

On this second capture of the city by force of arms, and without capitulation, the troops were clamorous to be permitted to plunder.  Amru again checked their rapacity, and commanded that all persons and property in the place should remain inviolate, until the will of the Caliph could be known.  So perfect was his command over his troops that not the most trivial article was taken.  His letter to the Caliph shows what must have been the population and splendor of Alexandria, and the luxury and effeminacy of its inhabitants at the time of the Moslem conquest.  It states the city to have contained four thousand palaces, five thousand baths, four hundred theatres and places of amusement, twelve thousand gardeners which supply it with vegetables, and forty thousand tributary Jews.  It was impossible, he said, to do justice to its riches and magnificence.  He had hitherto held it sacred from plunder, but his troops, having won it by force of arms, considered themselves entitled to the spoils of victory.

The caliph Omar, in reply, expressed a high sense of his important services, but reproved him for even mentioning the desire of the soldiery to plunder so rich a city, one of the greatest emporiums of the East.  He charged him, therefore, most rigidly to watch over the rapacious propensities of his men; to prevent all pillage, violence, and waste; to collect and make out an account of all moneys, jewels, household furniture, and everything else that was valuable, to be appropriated toward defraying the expenses of this war of the faith.  He ordered the tribute also, collected in the conquered country, to be treasured up at Alexandria for the supplies of the Moslem troops.