In response to determining that a target vehicle is at large, identification information associated with the target vehicle's license plate may be retrieved and used to generate one or more synthetic license plate images. The synthetic license plate images may be subjected to one or more transformation to cause them to resemble authentic license plate image captures and/or to mimic authentic license plate image captures from existing and operational ALPR system cameras. Target signatures may then be calculated from the synthetic license plate images. Upon capturing an authentic license plate image using an ALPR system camera, a signature of the authentic license plate image may be calculated. If a match is found between the signature of the authentic license plate image and a target signature, law enforcement may be alerted that the target vehicle was detected at the location of the ALPR system camera.