Sergeant Cordova Estelo sustained a lone but fatal stab wound in the chest. His assailant, identified as Manuel Ocenar, had to be shot in the knee by a NBP jail guard in order for him to be subdued.
Reports said the incident happened at around 8 p.m. inside the maximum security compound of the prison facility.
NBP Director Vicente Vinarao, in an interview with The Star, said a heated argument between Estelo and Ocenar led to a fistfight and eventually to the stabbing incident.
Vinarao said the two were actually buddies but for some reason, got into a quarrel and ended up trying to kill each other.
"Magkaibigan yan eh (They were friends)," Vinarao said, adding that the victim and the suspect, a convicted rapist, both worked for former congressman Romeo Jalosjos.
But Volunteers Against Crime and Corruption (VACC) founding chairman Dante Jimenez said his sources gave him a different story.
Estelo was allegedly trying to mediate a fight between two other inmates and was stabbed in the process.
Jimenez said his informants told him that Ocenar was also armed with a caliber. 32 handgun aside from the bladed weapon he used to stab the former military man.
But whether or not the death of the Aquino-Galman double murder convict was incidental or intentional, the VACC wants an investigation.
The group fears an effort to eliminate all 15 convicted soldiers of the Aquino-Galman case to prevent the re-opening of the 25-year-old case.
Jimenez said the VACC will also seek the transfer of the convicted soldiers to the minimum security compound as they already served the required number of years at the maximum security area and they all have good records, in so far as attitude inside the NBP is concerned.
"They are very important to the case kaya nga pinag-i-ingat sila eh (that is why they are being asked to take precaution). They should be moved from the maximum security compound," Jimenez told The Star.
All 15 soldiers were housed with other heinous crimes convicts and are allegedly always in danger considering the kind of crowd they are mixed with.
Jimenez said efforts to re-open the 1983 Aquino-Galman double murder case are still alive and the search for former captain Felipe Valerio, who fled to the United States after the twin assassinations continues.
Once found, Valerio will allegedly be able to shed light into what really happened during the Aquino assassination and who was responsible.
Jimenez said Valerio was the officer-in-charge of the van used by the soldiers who allegedly told the driver of the vehicle to just shut up and mind his own business when the latter noticed that he saw someone carrying a gun.