New York Fire Department
File photo: Engine Company 205 / Ladder Company 118 in Brooklyn Heights is viewed on September 11, 2015 in New York City. Spencer Platt/Getty Images

A fire that ripped through a New York house in the early hours of the morning has killed a woman and three children under 12. However the woman's husband managed to get two of their teenage children to safety, although they remain in a critical condition in hospital.

The blaze was first reported at 2.30am in Brooklyn's Sheepshead Bay neighbourhood on Monday (18 December).

New York City Fire Department said that the father had acted "very courageously" to get the teenagers to safety.

The mother was named as 39-year-old Aliza Azan and the three children as 11-year-old Moshe, seven-year-old Yitzah and three-year-old Henrietta.

The father and sons have not been named. It is understood that another relative was at the house at the time of the fire.

Fire Department Commissioner Daniel Nigro said that a smoke detector may have alerted two boys in the house to the fire although it is yet to be found. The cause of the fire is still being determined.

"So often, tragedy strikes at this time of year, and the holidays make it that much more difficult because our communities should be celebrating, not mourning," Nigro said.

"While this fire remains under investigation by fire marshals, we know that unattended candles, overloaded outlets and power strips, and many of the holiday traditions we all hold dear are so often the cause."

Even though fire fighters arrived within two and a half minute of the first report, the fast moving fire had already engulfed three floors and firefighters were met with flames at the front door.

New York Mayor Bill de Blasio said in a statement: "Our city is mourning the loss of three children and their mother in a fire early this morning in Sheepshead Bay. As a parent, it's impossible for me to imagine what this family is going through right now.

"During the holiday season, we all need to be cautious with decorations, electric lights, candles, space heaters and other items. We will continue working with FDNY to promote fire safety, especially during the winter months when there's an increased risk of fires."