New York, Dec 29 (IANS): At least 12 people, including a one-year-old infant, was killed after a massive fire broke out at an apartment building in The Bronx, New York City, media reports said.

Authorities said the death toll could still rise from the fire that began at 6.51 p.m., on Thursday and gutted the building in the Belmont neighbourhood near the Bronx Zoo, reports the New York Post.

"We're here at the scene of an unspeakable tragedy in the middle of the holiday season, a time when families are ­together," Mayor Bill de Blasio said during a press briefing late Thursday night.

"Tonight here in The Bronx, there are families that have been torn apart. This is the worst fire tragedy we have seen in this city in at least a quarter-century.

"There are four people critically injured who are fighting for their lives. Other serious injuries as well."

A law enforcement official said that the infant was discovered cradled in her mother's arms in the bathtub of one of the apartments. They were both dead.

According to Fire Department New York Commissioner Daniel Nigro the fire started on the first floor and quickly spread upstairs into the five-storey building with 25 apartments, reports the New York Post.

The commissioner said it was too early to determine what caused the fire.

New York Governor Andrew Cuomo tweeted: "We are closely monitoring the devastating fire in the Bronx. As always we are thankful for our first responders. Our thoughts are with the victims and their families tonight."

The fire stands to be the most deadly in New York City since 87 people perished in March 1990 in the infamous Happy Land social-club arson attack which took place less than a mile away from Thursday's location.