New York City authorities are trying to find answers to what started a deadly fire in the Bronx Thursday night. Mayor Bill de Blasio called it the "worst fire tragedy in this city in at least a quarter-century," and so far we know that at least 12 people are dead. Of those 12 people, at least three victims were children under the age of 10. In addition, there have been at least four more injuries. 

On Dec. 28, the first call about the fire in the Bronx came at 6:51 p.m. The New York City Fire Department (FDNY) responded within three minutes of receiving the call. 

As of Friday morning, there are many unclear details. For one, the entire cause of the fire is unknown.  However, according to CNN, there are a few things we do know so far: 

  • According to the New York City Housing Preservation and Development online records, there is at least one open violation reported in August 2017 for the building, indicating there was a defective carbon monoxide detector in a first-floor apartment, and one open violation for a defective smoke detector in the same apartment. Since 2004, the city received four complaints about the building, which didn't appear to be fire-related. 
  • The fire broke out on the first floor of the five-story building Thursday evening; firefighters extinguished it sometime before 10 p.m. The walk-up building contained 29 units. Victims died on various floors of the apartment building.
  • A 1-year-old, a 2-year-old and a 7-year-old are among those killed, according to the NYPD. Victims ranged in age from one to over 50.
  • Four people were critically injured and others were hurt, the mayor said. He added that it's possible that "we may lose others as well."

"This will rank as one of the worst losses of life to a fire in many, many years," de Blasio said in a Thursday press conference.

Thankfully, at least 12 people were rescued and are expected to survive, according to the mayor.

"This tragedy is, without question, historic in its magnitude," said Daniel Nigro, the city's fire commissioner. "Our hearts go out to every family who lost a loved one here and everyone fighting for their lives."

As we learn more about the fire and details continue to develop, we send our deepest condolences to those who were affected by this tragedy.