Dec. 28 (UPI) -- At least 12 people are dead after a fire in a Bronx apartment building Thursday night, New York City Mayor Bill de Blasio confirmed.
"Tonight in the Bronx we've seen the worst fire tragedy in at least a quarter of a century," de Blasio said on Twitter. "It is an unspeakable tragedy, and families have been torn apart."
De Blasio said 12 people were killed, including one child. Several others were critically injured.
"This is the worst fire tragedy we have seen in this city -- it will rank as one of the worst losses in a fire in many years," de Blasio said at a news conference.
De Blasio also said at least 12 lives were saved by members of the Fire Department of New York City.
According to FDNY Commissioner Daniel Nigro, the fire started on the first floor and quickly spread to the upper floors of the building. Nigro said people died on various floors and the ages of the victims range from 1 to 50.
The cause of the fire has not yet been determined.
"This tragedy is, without question, historic in its magnitude," Nigro said via Twitter. "Our hearts go out to every family who lost a loved one here and everyone fighting for their lives."
According to The New York Times, the building is a 100-year-old, five-story walk-up near Fordham University and the Bronx Zoo. It has more than 20 units.