Senior Fire Officer 3 Dante Mendoza of the Bacood fire station suffered a laceration near the left eye when a galvanized iron sheet hit him at the height of the fire.
The fire started at a three-story residential building owned by one Ernesto Villanueva along Anonas street at around 10:35 a.m.
The blaze quickly engulfed nine other houses made of light materials located along the railroad tracks, according to arson investigator SFO2 Wilson Tana.
Firefighters successfully prevented the blaze from reaching the nearby Polytechnic University of the Philippines.
The fire was finally placed under control at around 11:13 a.m. after reaching the fifth alarm.
Arson investigators are still determining the cause of the fire. Damage to property was placed at P300,000.