(CNN)An Ohio grand jury has decided not to return an indictment in the 2014 police shooting death of 12-year-old Tamir Rice, prosecutor Tim McGinty said Monday. Rice was holding a pellet gun when he was shot. It was "reasonable" to believe that the officer who killed the boy was facing a threat, McGinty said. The officer was in training outside a Cleveland recreation center in November 2014. The shooting sparked controversy given Tamir's age and the fact that he had a gun that resembled a handgun. McGinty called Rice's killing an "absolute tragedy." "But it was not, by the law...