Quezon City fire marshal Oscar Villegas identified the fatalities as Johnson Dy, 34; his wife, Tintin, 33; their daughters Snow, 5; and Sky, 1 and family nanny Vicky Torrefranco, 50.
The charred bodies were found in the masters bedroom of their unit at the Miami Condominium located at the corner of Samat and Don Jose streets in Barangay Sto. Domingo.
Another nanny, identified as Erika Espartino, 18, escaped unhurt from the burning building. She is now being questioned by investigators to shed light on the incident.
Villegas said the blaze started from the third floor of the townhouse unit at about 2:21 a.m. Fire reached the second floor before it was put out at about 4:45 a.m.
He said arson investigators as well as crime scene officers have started collecting evidence at the scene.
"We are trying to determine the actual cause of the blaze and determine if there was foul play involved."
Radio reports quoted Espartino as claiming the blaze started from Dys lighted cigarette in the master bedroom.