A method for detecting one or more target objects is provided including obtaining 2-dimensional imaging information and 3-dimensional point cloud information of a target zone. The method also includes determining a ground plane in the point cloud information and removing the ground plane to generate modified 3-dimensional information. Also, the method includes identifying a set of 2-dimensional candidate objects from the 2-dimensional imaging information, and identifying a set of 3-dimensional candidate objects from the modified 3-dimensional information. The method also includes determining, for each of at least some of the 2-dimensional candidate objects, a corresponding 3-dimensional candidate object from the set of 3-dimensional candidate objects. Further, the method includes modifying the 2-dimensional confidence measure for each of the at least some of the 2-dimensional candidate objects to generate fused confidence measures based on whether the 2-dimensional candidate object corresponds to a 3-dimensional candidate object.