The blast, which scattered debris across nearby rooftops, brought down the neighboring five-story buildings, with a total of 15 apartments, at about 9:30 a.m. (1330 GMT) on a largely residential Upper Manhattan block at East 116th Street and Park Avenue.
Clouds of thick smoke billowed from the rubble of the apartment buildings that sat above a ground-level church and a piano store in a largely Latino working-class neighborhood. Officials declined to give a number of people still missing.
Mayor Bill de Blasio, who rushed to the scene in East Harlem, where a cascade of twisted and burnt metal blocked the sidewalk and covered parked cars, said preliminary information showed the explosion was caused by a gas leak.
Officials at the press conference said the blast occurred 15 minutes after a resident in an adjacent building called Con Edison to complain of a gas odor.
Edward Foppiano, Con Ed’s vice president for gas operations, said that while the utility could not say for certain what caused the explosion, it was treating the incident as a gas leak issue. The utility most recently responded to customer complaint about a gas odor in the area last May, but the issue had been resolved, Foppiano said.
The National Transportation Safety Board said it was investigating the “gas explosion and subsequent fire.”
Metro-North Railroad, which had shut down train traffic moving through Manhattan while it cleared debris from the tracks announced late afternoon it had restored all commuter train traffic passing through the area.