The PSO is first a policeman and then a PSO. When the person whom they are providing security is indulging in crime before the eyes of the policeman it is his duty to arrest them. It is like the case of Salman Khans security guard who did not arrest Salman when he drove over the sleeping workers.
That PSO should be suspended first alongwith Lalloos sons and an inquiry should be ordered.
It is a matter of worry as to what would have happened if one of those were shot at or dead with the snatched service weapon.