Po said personal anger and the desire to get even could have been the reasons behind the incident.
The city police director bared it came out in the investigation that Glenn Octaviano, the lone fatality during the blast, was a problematic man before the incident.
The police official further revealed that aside from having family problems, Octaviano, a juice vendor here, was also harboring rancor against a policeman who kicked his pushcart during clearing operation last Monday.
Octaviano's glass container was reportedly broken when the policemen kicked his pushcart. The victim's family, Po said, was against Octaviano's minor live-in partner.
Po claimed they are now investigating where Octaviano got the grenade and who was the cop who kicked the victim's pushcart.
He said it could be possible that while Octaviano was on his way to the oval plaza, he had already removed the safety pin of the grenade and the lever was accidentally released resulting to the premature explosion.
"It was just an isolated incident. A case of accidental explosion and it was not terror-related," Po emphasized.
The family of Octaviano meantime refused to believe Po's statement.
Kris Octaviano, the victim's sister, told newsmen here that his brother has no family problem since a few days before the incident, he entrusted his P5,000 savings to her, which he was planning to use as down payment in buying a motorcycle.
Kris added that during the same instance she saw his brother giving a P1,000 allowance to their father.
"If it's true that our family had a gap or problem why did he entrusted his savings to me and why did he gave money to our father?" Kris asked.
Florentino Sanico, a street vendor and a close friend of Octaviano, told reporters that indeed his friend was harboring a grudge against the policeman who bullied them last Monday.
Sanico and Octaviano exchanged views while in drinking session a few hours before the blast.
Sanico claimed it was the first time he saw his friend drinking liquor. (Aquiles Z. Zonio)