In recent years, there has been considerable interest in Camera Sensor Networks (CSNs) as next-generation monitoring systems due to their ability of processing large amount of data. In this paper, we propose a 2-level hierarchical architecture for tracking multiple targets using Pan-Tilt-Zoom (PTZ) cameras. In this method, each camera can track moving targets by local communications with other cameras and the global communication with a coordinator which assigns a camera to a target to be monitored. We conduct a simulation to show that the proposed method can successfully achieve multiple tracking.