We are developing a device for radiation source identification based on 4π gamma imaging and Simultaneous Localization and Mapping (SLAM). The proto-type device equipped with a 3D LiDAR, a 4π gamma camera, and a 4π optical camera was mounted in an unmanned vehicle. 4π gamma-ray and optical images were measured during the movement of the device around 137Cs sources in thin barrier boxes. Combined with 4π gamma images and SLAM obtained by LiDAR data, both location and activity of each source were estimated.