An embodiment of the present disclosure is directed to a radioactive source tracking system adapted to determine in real time a spatial position of a gamma source in a volume, including a set of spatially distributed position sensitive detectors operable in real time arranged about the volume. The system includes a real time computer system adapted to calculate the spatial position per time stamp of the gamma source in the volume based on respective signals generated by the position sensitive detectors. In addition, the radioactive source is represented by a 3D or 4D data stream in real time. Other embodiments of the present disclosure are directed to a method for tracking a radioactive gamma source and a computer program product for causing a processor to determine a real time 3D or a 4D spatial position of a gamma source.