Task: Question Answering
Input (English): Passage: Hulagu died in 1265, and was succeeded by Abaqa (1234–1282), who further pursued Western cooperation. Though a Buddhist, upon his succession he married Maria Palaiologina, an Orthodox Christian and the illegitimate daughter of the Byzantine Emperor Michael VIII Palaiologos. Abaqa corresponded with Pope Clement IV through 1267 and 1268, sending envoys to both Clement and King James I of Aragon. In a 1268 message to Clement, Abaqa promised to send troops to aid the Christians. It is unclear if this was what led to James's unsuccessful expedition to Acre in 1269. James initiated a small crusade, but a storm descended on his fleet as they attempted their crossing, forcing most of the ships to turn back. The crusade was ultimately handled by James's two sons Fernando Sanchez and Pedro Fernandez, who arrived in Acre in December 1269. Abaqa, despite his earlier promises of assistance, was in the process of facing another threat, an invasion in Khorasan by Mongols from Turkestan, and so could only commit a small force for the Holy Land, which did little but brandish the threat of an invasion along the Syrian frontier in October 1269. He raided as far as Harim and Afamiyaa in October, but retreated as soon as Baibars' forces advanced. 
Question: What country attacked Abaqa's empire?
Output (English): Turkestan.