A method and system, for detecting closely spaced objects with data from an imaging sensor. A CFAR detector performs detection on the image data at a threshold level. A processor runs a first algorithm on exceedances above the CFAR threshold. The first algorithm is for single target detection and includes a local-max algorithm that identifies multiple exceedances within a 2×2 matrix of image data and only keeps exceedance with the maximum value. All other exceedances in image are single target detections. The processor runs a second algorithm that identifies multiple exceedances (single target detections) within a local regional area across the whole image. The regional area size may be a 3×3, 4×4, or 5×5 matrix depending on the specified CSO separations. This algorithm may use a regional moving window across the whole image. An alternative method using the indices of all the exceedances' (x,y) coordinates is also disclosed.