The present disclosure provides a method including memorizing a sequence of high-resolution images of a scene in a buffer, obtaining radiation emission readings from one or more photo detectors, detecting a suspected flash event based on processing the radiation emission readings from the one or more photo detectors. The method may further include that the detecting occurs at a first instant, retrieving from the buffer high-resolution images of the scene including at least one image that was captured prior to said first instant, and processing the high-resolution images of the scene to determine a geolocation of the suspected flash event.