1. A system for analyzing images of a scene to identify a target color, the system comprising: a thermal detector for obtaining a thermal image of the scene within a thermal waveband; at least one additional detector for obtaining at least one additional image of the scene at an additional waveband different from the thermal waveband; and a controller configured to: process the thermal image to identify portions of the scene having a temperature exceeding a threshold value; process the additional image to identify portions of the scene having the target color; and output a positive response if a same portion of the scene is identified in the thermal image and in the additional image.