The first fire hit a two-story residential house at 165 Ibarra street in Sampaloc at around 5 a.m.
Arson investigator SFO1 Emmanuel Gaspar said the fire struck the second level of the house owned by one Jose Cabrera and razed three more adjacent houses.
The fire reached fifth alarm before it was finally put out at around 5:30 a.m.
No one was injured in the Sampaloc fire.
Damage to property was initially placed at P400,000. The cause of the fire is still being investigated.
Six hours later, a second fire struck a two-story house located at the corner of Kagitingan and Tuazon streets in Tondo.
The fire reportedly started at the second floor of the house owned by the De la Cruz family.
The first floor served as depository of scrap cartons from the trading business of the family.
At the height of the fire, one Ricardo de la Cruz, 46, suffered lacerations on the leg and fingers after he was hit by a falling galvanized iron sheet while trying to extinguish the fire.
The fire was caused by faulty electrical wiring, according to arson investigator SFO1 Rodelio Nelvis.
Three adjacent houses were also razed.
The fire was finally placed under control at around 12:50 p.m. after reaching the fifth alarm.
Damage to property is still being ascertained as of press time.