When Edward finally arrived in Acre on May 9, 1271, he immediately sent an embassy to the Mongol ruler Abaqa. Edward's plan was to use the help of the Mongols to attack the Muslim leader Baibars. The embassy was led by Reginald Russel, Godefrey Welles and John Parker. Abaqa answered positively to Edward's request in a letter dated September 4, 1271. The historians Runciman and Grousset quote the medieval French "Estoire d'Eracles", a continuation of the twelfth-century Latin chronicle of William of Tyre:  In mid-October 1271, the Mongol troops requested by Edward arrived in Syria and ravaged the land from Aleppo southward. Abaqa, occupied by other conflicts in Turkestan, could send only 10,000 Mongol horsemen under general Samagar from the occupation army in Seljuk Anatolia and auxiliary Seljukid troops, but they triggered an exodus of Muslim populations (who remembered the previous campaigns of Kithuqa) as far south as Cairo. The Mongols defeated the Turcoman troops that protected Aleppo, putting to flight the Mamluk garrison in that city, and continued their advance to Maarat an-Numan and Apamea. When Baibars mounted a counteroffensive from Egypt on November 12, the Mongols had already retreated beyond the Euphrates, unable to face the full Mamluk army. In the summer of 1299, the Mongols under Ghazan successfully took the northern city of Aleppo and defeated the Mamluks in the Battle of Wadi al-Khazandar (also known as the 3rd Battle of Homs), on December 23 or 24, 1299. One group of Mongols under the command of the Mongol general Mulay then split off from Ghazan's army, and pursued the retreating Mamluk troops as far as Gaza, pushing them back to Egypt. The bulk of Ghazan's forces then proceeded to Damascus, which surrendered sometime between December 30, 1299, and January 6, 1300, but its Citadel resisted. Ghazan then retreated most of his forces in February, probably because their horses needed fodder. Ghazan also promised to return in November to attack Egypt. Accordingly, there existed a period of about four months, from February to May 1300, when the Mongol il-Khan was the de facto lord of the Holy Land. The smaller force of about 10,000 horsemen under Mulay engaged in raids as far south as Gaza, returned to Damascus around March 1300 and, a few days later, followed Ghazan back across the Euphrates.