Four more bodies were found overnight in the smoldering rubble of two upper Manhattan buildings leveled by a gas explosion that injured more than 70 people and spewed debris for blocks, bringing the death toll to seven.
Rescue crews brought in a backhoe and bulldozer and were digging through the debris Thursday for more buried victims as firefighters battled flareups in the wreckage of the two five-story buildings that collapsed Wednesday morning on 116th and Park Avenue.
The force of the blast was so strong that it registered on the Richter scale at just under .5, according to Columbia University. Smoke billowed into Central Park and could be seen miles away in midtown, and New Yorkers said they felt rumbles as far away as 150th Street. Closer to the collapse, groceries were knocked from store shelves and an ashy film covered streets, sidewalks and cars.
The only indication of anything wrong before the explosion was a call to Con Edison from a woman in a nearby building, reporting a strong odor of gas just minutes before the blast, the mayor and the utility said. But it was too late.
"This is a tragedy of the worst kind because there was no indication in time to save people," Mayor de Blasio said.
Three of the seven victims killed in the explosion have been identified as Griselde Camacho, 44, Carmen Tanco, 67, and Rosaura Hernandez-Barrios, 22. Three others, two men and one woman, have not been identified. It's not clear if the seventh victim, recovered Thursday morning, is a man or a woman.
Hospitals reported receiving 74 people injured, including one teen and one woman who were both critically hurt. The 15-year-old boy's skin was badly burned, and he had broken bones and internal injuries, doctors said. The woman, who was pulled from the debris, is being treated for critical neck and back injuries.
Most of the people who were injured are expected to survive. At Harlem Hospital, where more than a dozen people were treated, one man who suffered from smoke inhalation described passing out as he ran from falling debris.
"I just kept on going, just trying to get away," he said.
Another man was driving a cab near the Metro-North tracks when he felt the blast.
"He thought the train was falling on top of him, but that wasn't true," his son said. "His car got shattered but he's OK. He's shaken up."
Two on-duty FBI agents who were driving through the area at the time of the explosion were among those hurt, but their injuries were not life-threatening, the FBI said.
A woman who was at her home on 115th Street between Park and Lexington avenues said she heard the explosion and thought it was a bomb. The explosion was near where Metro-North tracks run through Harlem.
"I thought a train had exploded," said Marisa Aquino.
Another woman who said she was watching TV in her home about a block away said the explosion blew out her windows.
"All my windows shattered and I didn't know what it was," she said on NBC 4 New York. She said first responders soon arrived at her building and ordered everyone out.
"It sounded like a bomb. That's what it really sounded like," Trey Dey, a laborer who was working in a nearby basement when the buildings exploded, told NBC 4 New York.
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A sinkhole developed from a water main break likely caused by the explosion, complicating efforts Wednesday night. The FDNY said crews had to repair the sinkhole before heavy equipment could be brought to the scene for cleanup and search efforts.
Officials cautioned the firefighting and cleanup process would take time.
The Buildings Department said one of the collapsed buildings had six units and the other had nine. One of the buildings had work done in June for 120 feet of gas piping, records show. It has no violations on record.
The other building just to the north had one violation from 2008 related to vertical cracks in the rear of the building. The city said a fine was paid but it was not clear that the condition had been corrected.
Con Edison described the building's gas main as an 8-inch iron and plastic main. In 2011, 70 feet of it was replaced during an excavation project.
The explosion blew debris onto the elevated tracks of the Metro-North tracks above Park Avenue, causing a shutdown of service in both directions. Service was restored late Wednesday afternoon after tracks were cleared of debris and inspected for structural integrity, the MTA said.
The Department of Environmental Protection is monitoring air quality in the area. The city's health department says smoke from the fire has largely dissipated and that respiratory irritation from any smoke is usually short-term in healthy people.
The NTSB said it was joining the investigation. The agency probes pipeline explosions as well as transportation disasters.
The NTSB says it will examine Con Edison's handling of customer complaints, the oversight of Con Edison by federal and state officials, and any evidence of possible third-party damage from digging, among other things.
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