Bureau of Corrections (BuCor) director Ricardo Macala identified the inmate as Jose Manansala, a member of the Genuine Ilocano Group (GIG).
The other fatality was identified by NBP Hospital chief, Dr. Maria Luz Villanueva, as one Cesar Corpuz.
Villanueva said three inmates sustained stab wounds in the body and are now at the Medical Center of Muntinlupa for further medical examination.
Two others who sustained minor injuries have been sent back to their brigades inside the compound, Villanueva said.
Macala said the incident happened at around 7:20 p.m. near the GIG’s basketball court.
For unknown reason, Manansala drew out an improvised ice pick and attacked his fellow GIG members.
According to Macala, Manansala had been in and out of the NPB’s detoxificaton and mental ward 16 times.
Other GIG members mauled Manansala, Macala said, resulting to his death.
Manansala and Corpuz were pronounced dead on arrival at the NBP Hospital, Villanueva said.
Earlier on Thursday, an inmate at the maximum security compound escaped.
Macala said jailguards would be investigated as a "routine." – Nikko Dizon