Abstract: A vehicle monitoring system configured to detect and localise an anomaly in or on a vehicle. The system includes a detector configured to detect an invisible indicator originating from or emitted by the anomaly and generate a detection signal associated with the invisible indicator, a camera configured to capture an image of the vehicle, and a controller configured to process the detection signal generated by the detector and the image of the vehicle captured by the camera. The controller is further configured to, based on processing of the image and the detection signal, generate a visualisation of the detection signal overlaid onto the image of the vehicle for localisation of the anomaly in or on the vehicle.