Police identified the victims as Lourdes Arpon-Rivera, 72, owner of the unit inside Powerline Subdivision, Talipapa in Bagong Silang and her stay-in helper Genda Batucan, a native of Butuan City.
Batucan, who was found naked lying in a pool of blood, could have been sexually abused before the suspects killed her, police said.
Investigators said the robbery and twin murder could have occurred between 1 a.m. to 3 a.m., but was only reported to police at around 5:30 in the morning.
Superintendent Dionicio Borromeo, chief of the Caloocan City police Station Investigation and Intelligence Division, said a neighbor got curious when Rivera failed to open their store.
Borromeo, who rushed to the scene of the crime, said Carmen Lozada called a police sub-station for assistance after finding the bodies of the storeowner and her maid.
The store is on the first floor of the two-story unit which is situated inside the public market, police added.
Investigators said the victims had multiple stab wounds in various parts of their body.
The burglars ransacked the victims’ house and took valuables, personal belongings and an undetermined amount of cash before fleeing the scene.
Investigators said the two may have been roused from their sleep inside their cramped room when the burglars, believed to be members of the notorious Akyat Bahay Gang, sneaked inside. Rivera and Batucan may have confronted the burglars and put up a fight, which cost them their lives.
Sub-station 3 operatives under Chief Inspector Lino Garcia, who has jurisdiction over the Bagong Silang area, are conducting follow-up operations.