(UPDATE) Grenade explodes in Isabela; peace advocate hurt

MANILA, Philippines (Xinhua) - A grenade exploded inside the headquarters of the Philippine Army's 5th Infantry Division in Gamu, Isabela this morning, wounding a peace advocate.

The grenade was placed under a van and it exploded when the driver began turning the steering wheel at 9:45 a.m., said Rowena Abayon, the division's public affairs officer.

The explosion injured one of the van passengers, identified as Felipe Carino, vice chairman of the Cordillera Forum for Peace and Development Inc. He sustained injuries in the lower part of his body and was promptly treated at the military hospital.

Abayon said the van's front tires were blown out while its front windshield was shattered as a result of the explosion.

Investigations are still going on to identify the perpetrator.