Police identified the fatality as Leo Ismael Dulce, driver of Superintendent Franklin Mabanag and a resident of 18th Avenue in Murphy, Cubao.
CPD director Chief Superintendent Napoleon Castro said Dulce was rushed to the East Avenue Medical Center, but died hours later due to massive head injuries.
Initial investigation disclosed that the incident happened around 10:15 p.m. last Sunday inside a comfort room on the third floor of the CPD headquarters in Sikatuna Village.
Castro told The Star that Dulce was asked by Mabanag, head of the CPD-District Intelligence and Investigation Division, to get the fragmentation grenade, which would be turned over to the Explosives and Ordnance Division (EOD), from the comfort room.
Castro said that the fragmentation grenade was recovered by the group of Mabanag in one of its operations and was kept inside the comfort room, which he described as a small room where seized firearms are likewise placed for safekeeping.
He noted that Mabanag was inside a room nearby typing a report for the turnover of the fragmentation grenade when the explosion occurred.
Raw information received by Castro revealed that the grenade accidentally fell and consequently went off.
An ocular inspection resulted in the recovery of a grenade safety lever in the room.
Castro said that he ordered a thorough investigation on the incident to determine the events leading to the tragedy.