The fire started about 3:40 a.m. Friday on the 200 block of Woodlawn Avenue in Hamilton Township, according to Mercer County Prosecutor Angelo J. Onofri.
The quickly-moving blaze caused a partial roof collapse in a two and a half story, wood-frame duplex, and reportedly spread to an adjoining residence, initial reports said.
A baby girl and the woman in her 40s were found dead inside the duplex, Onofri said.
A spokeswoman for the county prosecutor later confirmed that the victims were related: a grandmother and her grandchild.
At least three other people were hospitalized with injuries that included serious burns.
The cause of the fire is unknown at this time, as are the circumstances surrounding the deaths, the prosecutor said.
An investigation is being conducted by the Mercer County Prosecutor’s Office Arson Unit, the Mercer County Homicide Task Force and the Hamilton Police Division.
Anyone with information is urged to call Detective Anthony Sturchio at 609-989-6406. Information can also be emailed to mchtftips@mercercounty.org.
Additional photos of firefighters battling the fatal fire can be seen by clicking on BreakingNewsOfTrenton
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