1. An imaging system comprising: a main detection unit, configured to acquire reflection-based images of an environment to be imaged, said main detection unit comprising: at least one light source, configured to emit light pulses toward said environment; and at least one gated image sensor, configured to receive reflections of said light pulses reflected from a selected depth of field (DOF) in said environment, and to convert said reflections into a reflection-based image, an auxiliary detection unit, configured to acquire emission-based images of said environment, said auxiliary detection unit comprising: at least one thermal sensor configured to detect infrared radiation emitted from said environment, and to generate an emission-based image, an image processor, configured to process and to detect at least one region of interest (ROI) in at least one acquired reflection-based image and at least one acquired emission-based image; and a controller, configured to adaptively control at least one of detection characteristic of at least one of: said main detection unit; and said auxiliary detection unit, based on information obtained from the other one of: said main detection unit; and said auxiliary detection unit, wherein said image processor is further configured to detect at least one object of interest in at least one of: said reflection-based image; and said emission-based image.