Despite increasing popularity, Location-based Services (LBS) (e.g., searching nearby points-of-interest on map) on mobile handheld devices have been subject to major privacy concerns for users. The existing third-party privacy protection methods hide the exact location of users from service providers by sending cloaking regions (CR) that contain several other user locations in the vicinity. However, this has not ensured LBS full immunity from the privacy concerns. In this paper, we describe a serious privacy problem of LBS called multi-query attack. In this attack, the exact location of the service requester can be inferred by the adversary through obtaining cloaking regions that are shrunk or extended in subsequent queries. This problem can be addressed by judiciously retaining, over a period of time, the cloaking regions for the same set of users. Most methods in the literature are weakened for considering only a static snapshot of users during evaluation. Thus, any update due to us...