The cause of a massive explosion and double building collapse in East Harlem Wednesday morning that left at least six people dead and dozens injured remains unclear as responders search through the debris for more possible victims.
The blast occurred at around 9:30 a.m. on East 116th Street and Park Avenue.
More than 250 firefighters were called to the scene.
The two five-story residential buildings, located at 1644 and 1646 Park Avenue, also housed the Spanish Christian Church and piano repair shop on the ground level.
Police say that 44-year-old Griselde Camacho, 67-year-old Carmen Tanco and 22-year-old Rosaura Hernandez-Barrios were killed in the explosion and collapse.
All three lived at 1644 Park Avenue, according to police.
The New York City Fire Department confirmed a fourth death shortly before 1 a.m. Thursday and a fifth death and sixth death shortly after that.
Hunter College officials said that Camacho was a public safety officer at the university.
Fire marshals and the New York City Police Department say there are still residents of the buildings that are unaccounted for.
The city had to evacuate two buildings and several apartments in the area to help firefighters.
However, the Department of Buildings is stressing that the structural integrity of the surrounding structures was not impacted by the explosion.
The deli on the corner of East 116th Street and Park Avenue and the building immediately next to the one that collapsed remain completely evacuated as of midnight Wednesday.
Eight apartments inside 91 East 116th Street and 18 apartments in 16-48 Park Avenue have been cleared as well.
The American Red Cross has set up a support center near the scene of the collapse at P.S. 57, a school on 115th Street between Lexington Avenue and Third Avenue.
"We're seeing around 50 people in our reception center as a result of this disaster," said Josh Lockwood, regional CEO of the American Red Cross. "We're providing shelter. We're making a meal right now, we're providing food right now, and we also have mental health counselors that are helping families cope with this tragedy."
The Red Cross is supporting emergency responders and any families affected by the explosion.
Focus has turned to the rubble after firefighters took several hours to extinguish the blaze.
The FDNY is removing debris to make sure nobody is trapped underneath.
"The building is in a very precarious position," said Fire Commissioner Salvatore Cassano. "We want to make sure that everybody that's in there, first responders are safe. It's been a great interagency response between OEM, police, fire, buildings, but it's going to be a long, extended operation, and we want to make sure that we can get through that debris as quickly as possible."
Rain could also add to the challenge of cleaning up the scene.
Mayor Bill de Blasio reiterated that the number of those unaccounted for will be fluid throughout the response.
"We don't want to speculate on the number of people who might be in the building and their situation until we have the ability to get closer and deal with that rubble," de Blasio said. "I want to be very careful. We're saying there's a number of unaccounted for people. Some may well be safe and sound elsewhere in the city and just aren't reachable. God forbid there are some in that building. It'll take some time to get in there and know for sure."
Cassano says rescue workers will be going through the rubble pile brick by brick.
The city says that a sinkhole has developed right in front of one of the collapsed buildings, which has hampered the investigation, as investigators won't be able to bring in heavy equipment to sift through the debris until the hole is stabilized.
A total of 15 apartments were located inside the collapsed buildings.
Despite heavy smoke earlier in the day, fire officials say there are no air quality concerns beyond the immediate collapse zone.
Mount Sinai Hospital said that as of 10:30 p.m. Wednesday, 19 out of 26 patients connected to the explosion and collapse have been treated and released.
One patient remains in critical but stable condition.
Mount Sinai's director of emergency management said that the critically injured woman was found in the rubble with a head injury.
Six others are still being evaluated.
The head of emergency says about half of all injuries were walk-ins, while the other patients were brought in by ambulance.
Doctors say most injuries were minor with patients being treated for cuts, scrapes, and smoke inhalation.
Harlem Hospital said that it treated 13 patients with injuries connected to the explosion, but only three remained in the hospital as of midnight Wednesday.
According to Harlem Hospital, three of their 13 patients were children.
One of the children is in critical condition.
NewYork-Presbyterian/Weill Cornell Medical Center said it treated and released 11 patients with injuries related to the explosion and collapse.
Metropolitan Hospital Center said that it treated and released 18 patients with minor injuries ranging from breathing problems to minor cuts and bruises.
According to Metropolitan Hospital Center, two of their patients were children. The children were 3 months old and 10 years old.
Metropolitan Hospital Center says that six patients came by ambulance and the other 12 walked in on their own.
The Federal Bureau of Investigation says that two of its agents were among those injured in Wednesday morning's blast.
Bureau officials say they were driving by at time of the explosion.
Both are said to have suffered non-life-threatening injuries.
Four investigators from the National Transportation Safety Board are looking into the natural gas pipeline involved in the explosion.
A spokesperson said that the board will spend three to five days investigating the site after emergency responders finish their work.
He said that they will look into Con Ed's call system and method for handling complaints of gas odor.
"We'll be looking at Con Edison's integrity management system. We'll be looking at their call system to see how they handle complaints, phone calls reporting odor of gas," said Robert Sumwalt of the NTSB.
He also said that they will be looking into whether the age of the gas main on that block-long stretch of Park Avenue, part of which dates back to 1887, had anything to do with the explosion.
"We've had a long-standing concern about cast iron pipe, and we are certainly looking at that," Sumwalt said. "Just this morning, we had a briefing to our staff talking about a pipeline accident in Birmingham, Ala. that did involve cast iron pipe. There was a cast iron pipe explosion in Allentown, Pa. three years ago. So this is something that we're very interested in."
He also said that the NTSB will investigate federal and state regulatory officials and look for evidence of damage to the pipeline by a third party.
"We want to find out not only what happened, but we want to find out why it happened, and our whole objective for being here is to make recommendations to make sure that something like this never occurs again," Sumwalt said.
Michael Clendenin, a Con Ed spokesperson, says that at this point, the age of the gas main is not a factor.
"It's not necessarily age that's the overriding factor with some of this equipment. It's the condition of the environment that the gas pipeline sits in, do you have multiple gas leaks from before, the soil that it sits in, the environment, all of those things come into play as to whether the condition of the pipe is good," Clendenin said. "From every record that we have on this block, there's nothing indicating that there's anything wrong with the condition of the pipe."
Several residents on the block at Park Avenue between 116th Street and 117th Street said that they had been smelling an odor of gas for at least a day and had called to complain about it.
However, Clendenin says that after checking the Con Ed logs, they have no record of any calls to Con Ed complaining of a gas odor until 9:13 a.m. Wednesday, which was 18 minutes before the explosion took place.
"We don't have any records of anyone calling us prior to today. We've got no 311 referrals or 911 referrals. If they were smelling gas, we certainly would have expected they would call," Clendenin said. "We respond to every call of an odor, of a gas odor immediately."
The Metropolitan Transportation Authority says that Metro-North service has been restored to and from Grand Central Terminal.
Service was suspended in and out of Grand Central for hours after the explosion Wednesday.
The MTA says that the explosion sent debris onto its elevated tracks on Park Avenue.
For the latest updates, visit mta.info.
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TWC News: At Least Six Dead, Dozens Injured in East Harlem Building Blast
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