NEW YORK: Investigators in New York City searched early on Friday for the cause of an apartment fire that killed 12 people including four children in the city’s deadliest blaze in at least a quarter of a century.

The fire broke out a little before 7pm EST (midnight GMT) on Thursday on the first floor of a brick building and quickly spread upstairs, killing people on multiple floors, the New York City Fire Department said.

“We’ve lost 12 people and we could lose more,” Mayor Bill de Blasio, who visited the scene of the fire, told CNN in a Friday morning interview. “Some are still fighting for their lives. It’s a horrible tragedy.”

Children ages 1, 2 and 7 died along with four men and four women, local media reported.

An unidentified boy also died.

A child playing with a stove may have caused the fire, de Blasio said on Friday.

“What we think at this point is that unfortunately it emanated from an accident, a young child playing with a stove on the first floor of the building,” de Blasio said in an interview with WNYC radio.

“I know there were concerns raised about the building itself,” de Blasio told WNYC. “Based on the research we have at this moment, it does not appear there was anything problematic about the building or the fire safety in the building.”

The building is in the Belmont section of the Bronx, a primarily residential, close-knit neighbourhood known as the “Little Italy” of the borough, near Fordham University and the Bronx Zoo.

Authorities said firefighters rescued 12 people from the building and four people were in the hospital in critical condition.

More than 160 firefighters responded to the four-alarm blaze.

The building, with 26 apartments, has at least six open building code violations, according to city records.

One violation was for a broken smoke detector in an apartment on the first floor, reported in August. It was not clear if the detector had been fixed or replaced or whether it had played any role in the fire.

“The building owner, the building manager is supposed to make sure that all those basic safety precautions are in place,” de Blasio said, when asked about the violations. He cautioned against speculation while the fire department investigated the cause.

New York City is undergoing a bitter cold snap with temperatures in the low-teens Fahrenheit and high winds, which according to one media report, stoked flames inside the building as residents flung open doors and windows.

Wherever fire hoses were sprayed, the ground was covered with sheets of ice, according to a NY1 reporter.

Two of the dead were found in a bathtub, according to cable news channel NY1.

“People were screaming, and that’s how we knew there was trouble,” eyewitness Kimberly Wilkins told WCBS television. “People were screaming, ‘Fire! Help! Fire! Help!”

The building is in a poor section of the Bronx, where roughly one-half of residents earn less than the US poverty threshold, according to the US Census Bureau.

One witness, Rafael Gonzalez, who lives across the street from the engulfed building, told WCBS he saw some youths on a fire escape of the burning building.

“What woke me up was the smoke, because I thought it was my building,” he said.

It was the deadliest fire in the city since an arsonist torched a Bronx nightclub in 1990, killing 87 people inside the venue that did not have fire exits, alarms or sprinklers, the New York Times reported.

Reuters