Abstract: A system, method, and computer program product for determining a trajectory of an item includes segmenting surveillance point data of sensors, by sensor, into track segments for the item, associating the track segments for the item in a segment group for the item, and fusing the track segments in the segment group for the item into a synthetic threaded track for the item. The fusing may include filtering of the track segments for the item across track segments. The filtering across track segments may be based on a weighting of the point track data of the track segments for the item. A system for determining a trajectory of an item may include a processing device configured to execute a threaded track process to convert a data set of surveillance point data into a synthetic threaded track for the item.