A gas leak triggered a large explosion in East Harlem on Wednesday morning, destroying two buildings, killing two people and wounding at least two dozen others. More than 12 people remain missing, according to the authorities.
Firefighters were still battling flames in the afternoon and prepared to look through the debris for survivors, most likely a delicate operation that could last into the night.
All train services in and out of Grand Central terminal were suspended as a result of the incident next to its tracks.
TV footage showed debris strewn across the street and smoke pouring out of the collapsed building.
"It was an explosion and a building collapsed," a spokesman for New York Police Department told AFP, giving no further details. Scores of firefighters have been dispatched to the scene.
"The call came at 9:34 am (1334 GMT). It is a residential building. The New York Fire Department is in the process of extinguishing the fire," another police spokesman added.
The New York Fire Department told AFP that 168 fire fighters and 39 different units had responded to the explosion.
A witness told CBS that "a lot of people" lived in the six-storey building, including one of her friends.
"I'm scared, I'm scared. I came out to see the situation," she told the channel from behind the security cordon at the scene.
"I'm very scared. I'm shaking. I'm asthmatic and I'm not supposed to be here. I just came," she added.
Another witness who lived across the street told the channel he saw the building on fire and that his relatives living further way also felt the blast.

"I saw a lady running with no shoes on. It was crazy. It was like a war zone," he said.

"First of all I thought it was an earthquake. I got calls from my family who felt it too and that was all the way up town. Man, it was crazy," he added.

The Metropolitan Transportation Authority announced it had suspended all train service in and out of Grand Central Terminal until further notice due to the explosion next to its tracks.

"Please listen for announcements at your station and check back here for updates/alternate service information," said an emergency notice published on its website.