At least two women are dead and two dozen people injured after a "major explosion" ripped through an East Harlem apartment building Wednesday morning, New York Mayor Bill de Blasio said.
The blast, fueled by a gas leak, erupted in a five-story building at East 116th Street and Park Avenue about 9:30 a.m., officials say. The explosion caused the building and one next door to collapse, flung debris onto nearby train tracks, cars and the sidewalk, and sparked a five-alarm fire that could be seen from blocks away.
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"Very heavy impact on the surrounding buildings," de Blasio said at a press conference. "This is the tragedy of the worst kind, because there was no indication in time to save people."
The mayor confirmed that the bodies of two women, who have not been identified, were found at the scene. At least 24 other people were hurt, including two with "serious life-threatening injuries," five with "serious non-life-threatening injuries," and 15 with minor injuries, the FDNY said.
Officials had initially reported that a man had been found dead at the scene..
"We know we lost two people already," the mayor said. He also warned that toll could rise. "There will be a search through the rubble of the building, as soon as the fire is put out, looking for those who are missing individuals.
A hotline will be set up for anyone seeking information on relatives or loved-ones who may be missing, he added. For now, people can call the city's main information line, 311.
"Every effort is being expended to locate each and every one of these individuals," de Blasio said.
The only apparent sign of danger came just 15 minutes before the blast. The utility Con Edison received a report of an apparent gas leak at the building, located at 1646 Park Ave., home to residential units and a piano store on the ground floor.
"Con Ed dispatched a team immediately to respond. The explosion occurred before the team arrived," de Blasio described.
Nearby residents and workers were rocked by the blast.
"The first thing I heard was a boom. The next thing I saw was the smoke," said Anthony Ferguson, who told news site DNAinfo.com New York that he was knocked to the ground by the explosion. "I saw bricks raining down on the church."
A church sits next door to where the explosion erupted.
Firefighters arrived at the scene at 9:33 a.m., where "they were faced with a very heavy fire condition," FDNY Commissioner Salvatore Cassano said. "Debris covering the sidewalk and a couple vehicles in the street. They quickly transmitted an alarm for a major collapse response."
As many as 250 firefighters from dozens of units responded. Three hours later, they were still working to put out the blaze. Con Ed workers were also breaking through the street to shut down gas lines to the building.
"Once the fire is under control and extinguished, we'll start with surface removal," Cassano said. "Check that there's nobody on the sidewalk or the street."
The property and those nearby he said, were "in a very precarious position."
Going through and eventually cleaning up the scene will "take quite a bit of time," de Blasio said, one requiring heavy equipment such as backhoes and cranes.
"This is going to be an extended operation," the mayor described.
The MTA suspended service along the Metro-North regional line, which runs to and from Grand Central Terminal about 70 blocks south, due to debris on the tracks. The agency also slowed subway trains along the 4, 5 and 6 lines on Manhattan's East Side.
Updated on March 12, 2014: This story was updated to reflect new information from the NYPD, FDNY and New York Mayor Bill de Blasio about the explosion and its toll.