A raging fire broke out in a two-story, two-family home in east New York, killing four people living on the 2nd  floor of the home, three of them children ranging in age from 11 months to 7 years.

The children's father also perished in the blaze and authorities are still trying to locate the mother of the family, Jessica Duell, who was not present at the home at the time it went up in flames.

One child living on the second floor who escaped with her life sustained serious injuries. Sapphire Terry, age 5, was taken to the burn unit at Westchester Medical Center for treatment and remains there in serious condition.

The residents occupying the first floor of the wood-frame house on Hulett Street in Schenectady, NY were awakened by fire alarms that went off after the fire ignited at around 4:30am. Three children and four adults escaped unscathed from the 1st floor apartment.

Shane Conway, one of the 1st floor residents says he was woken by screams from his stepfather's girlfriend as the fire began to spread.

"I got up, got everyone out, made sure my son got out," Conway told the Star Tribune in an interview.

Krystal Ashline, a friend of the family that resided on the 2nd floor said that she was very close to them, that her children often played with the young victims and that the father of the family was a great dad who took on the majority of parental responsibilities, according to the newspaper.

"It's a tragedy," Ashline said. "It just broke my heart."

Fire investigators in the city are working with state and federal authorities to determine the cause of the fire. Fire Chief Michael Della Rocco says the home will have to be condemned and demolished.

The inferno on Hullet Street was the third fire of the night in Schenectady, a city of 66,000 residents just west of New York State capital Albany. An investigation will look into whether the three fires were related, though any connection is highly unlikely, Della Rocco told reporters.