Locals in the Syrian Kurdish city of Kobani voice fears of a possible return by the Islamic State (ISIS) to the region after its sleeper cells attacked a security center held by the Internal Security Forces of North and East Syria (Asayish) in the city of Raqqa on December 26 in which two fighters of the Syrian Democratic Forces (SDF) and four members of the Asayish were killed, according to a statement released by Asayish.