A thunderous explosion in East Harlem sent "people flying out the windows," killing two women, injuring 18 and leaving two buildings in rubble Wednesday morning, according to the Fire Department and witnesses.
Mayor de Blasio authorities said the search continued for “a number” of people still unaccounted for three hours after the blast at 9:31 a.m.
“There was no warning in advance,” de Blasio said at the scene, adding there was no indication of foul play.
"It’s a tragedy of the worst kind because there was no indication.”
The mayor was flanked by Police Commissioner Bill Bratton and Council Speaker Melissa Mark-Viverito, whose district office is less than a block from the blast.
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Officials said 250 firefighters were fighting the five-alarm blaze where the two five-story buildings containing a piano store and Spanish Christian Church once stood. One building had six apartments, the other nine, according to de Blasio.
Jessica Ortega said her brother-in-law, Alexis Salas, lived in one of the buildings. She feared he was among the dead.
"We are very worried. We don't know what happened to him," she said.
A law enforcement source said the cause appeared to have been a gas explosion.
Residents of a building neighboring the site had complained of gas at 9:13 a.m. — 18 minutes before the explosion, Con Edison spokeswoman Elizabeth Matthews said.
Con Ed workers “arrived just after the explosion occurred,” Matthews said.
Fire Commissioner Sal Cassano said first responders narrowly avoided being caught by the blast.
“If we were here five minutes earlier we may have had some fatalities among fire fighters,” Cassano said. “Not being here may have saved some lives.”
Ashley Rivera, 21, said an odor of gas had lingered on the block for weeks.
"We saw people flying out of the windows. Those are my neighbors," said Rivera, holding back tears.
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Angelica Aguiler, 25, said she was asleep in her sixth-floor apartment when she felt the building quake.
“The window exploded. I was trying to get out but the door wouldn't open,” said Aguiler, describing her terror as neighbors tried in vain to help her escape.
“I called my stepmom and told her I was trapped. I couldn't get out!"
It was her stepmom, Melinda Cruz, 42, that finally rescued Aguiler.
“I had to sneak in through the back of the building. I got to her and opened the door. I hugged her," said Cruz.
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The fire began inside the Absolute Piano store at 1646 Park Ave. and was followed by the blast, witnesses told the Daily News.
Windows of nearby storefronts were shattered.
Children's toys and school books were mixed in with the rubble. At least three cars appeared to have been driving by the building when it blew. Firefighters used tools to rescue people trapped inside their rides.
Other smokeaters sifted through the rubble looking for victims as others continued to douse the flames. Bystanders lingered with dust on their coats.
A school behind the buildings was evacuated.
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A firefighter on the scene said that a building at the corner of East 117th St. and Park Ave. had become unstable as a result of the collapse.
Anthony Ferguson, 58, said he saw a man run into the burning building — and then be violently ejected onto the street by the force of the blast.
“He flew back!” said Ferguson, adding he saw first responders pull another man from the debris.
Mustafa Shohataa, 27, was standing on the south side of East 116th St. when he felt a wave of air followed by two explosions.
"I felt it like a breeze and the noises came and stuff started falling from the sky,” Shohataa said. “Smoke filled the street and people were running. I thought a train came off the tracks…It felt like the world shook.”
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Mitch Abreu, 23, was working at Milciades Barbershop nearby when he said he heard two explosions that shook the shop.
"It was loud, like boom, boom!" he said. "It rocked the whole block. A window blew out of the other shop down the street. It looked like the towers all over again. People covered in dust and covering their mouths."
Aisha Watts said she was using the bathroom at 1652 Park Ave. in a neighboring building when she heard the blast, which ripped part of her apartment apart. She was miraculously unscathed, but terrified.
"I thought it was a train derailment. Everything was shaking...I thought God was taking me home!" said Watts, 37. "We have no windows, no walls."
Rubble from the destroyed buildings spilled into Park Ave. and smoke choked the blocks surrounding the chaotic scene in East Harlem.
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“It was a big hole in the middle of the two buildings!” said Sam Krebs, 24. “A big cloud of smoke covered where the building used to be.”
Metro-North service was suspended in both directions. Glass from the blast littered the tracks and a law enforcement source guessed it could be hours before limited service resumed.
The MTA said 4, 5, and 6 trains were running at slow speeds due to concern about "vibrations" from the collapse.
A spokesman couldn't say when Metro-North service would resume. After debris is removed from the tracks, signals and other equipment will have to inspected and tested before trains can roll again, MTA spokesman Sal Arena said.
Congressman Charlie Rangel was presiding over a House Ways and Means Committee hearing in Washington when he heard the news.
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“It was just shocking," he told the Daily News.
“It's like being on the job and someone tells you your house is on fire and you have no idea of the casualties, who's there.”
The White House said President Obama had been briefed on the explosion that witnesses said was heard as far away as First Ave.
The history of one of the collapsed buildings hints at possible factors in the explosion.
Last June new gas pipe was supposed to be installed at one of the buildings that collapsed, 1644 Park Ave., records show. A Buildings department permit was issued to New York Heating to install 120 feet of gas pipe along the outside of the building connecting to a fifth-floor stove. An employee who answered the phone at New York Heating couldn’t say when the job was complete and if it was inspected by the fire department.
Several years ago the buildings department issued a violation against the building next door, 1646 Park Ave., after inspectors discovered the building’s rear wall contained a dangerous vertical crack “which is hazardous to the safety of the structure,” records show. The owner of the building, listed as Carl Demler, was issued a violation in August 2008. He apparently paid a $1,335 fine but there’s no record of compliance since.
The Buildings Department also received a complaint in 2008 that a fence had been erected blocking the second egress off the fire escape at 1644 Park Ave. but no violations were issued because inspectors determined there was a second egress through the basement.
On Jan. 14, tenants of Apt. 2 at 1646 Park Ave. complained to city housing inspectors about cracks in the walls and ceiling throughout the apartment, which could indicate there were structural problems there. Housing inspectors issued 13 violations for a variety of problems there, including missing smoke and carbon monoxide detectors and blocked fire exits. The violations remained unresolved as of Wednesday.
With Annie Karni, Pete Donohue, Joe Kemp and Edgar Sandoval