In 1259 the Mongols captured the Syrian city of Damascus, and eventually in 1260, Aleppo. The Mamluk sultan Saif ad-Din Qutuz looked to ally with the Franks, who declined. In September 1260, the Mamluks defeated the Mongols at the Battle of Ain Jalut, shortly after Qutuz was assassinated at Al-Salihiyya, and according to various sources his successor Baibars was involved in his murder. (Baibars "came to power with [the] regicide [of Qutuz] on his conscience" according to Tschanz.) Despite this, Baibars was named sultan, and in 1263 sacked Nazareth, threatened Antioch with invasion, and appeared before the walls of Acre. In January 1265 Baibars launched an offensive against the Latins, starting with Acre, the capital of the remnant of the Kingdom of Jerusalem, but was unable to take it, but defeated the Crusaders in many other battles in Arsuf, Athlith, Haifa, etc. And in 1268 Baibars besieged Antioch, capturing the city on May 18. Baibars promised to spare the lives of the inhabitants, but broke his promise and razed the city, killing or enslaving nearly the entire population upon their surrender.