NEW YORK (CBSNewYork/AP) -- Someone may have improperly tapped a gas line before an explosion that leveled three apartment buildings and injured nearly two dozen people, Mayor Bill de Blasio said Friday as firefighters soaked the still-smoldering buildings and police searched for at least two missing people.
"There is a possibility here that the gas line was inappropriately accessed internally by people in the building,'' but officials need to get access to the wreckage to explore it further, de Blasio said. He wouldn't say more about why officials believe that's a possibility.
Preliminary evidence suggested that an explosion amid plumbing and gas work inside the building was to blame.
Inspectors with utility Consolidated Edison had been to one of the now-destroyed buildings about an hour before the blast in the East Village to check on some ongoing work to upgrade gas service there. The utility said the work didn't pass inspection, so gas wasn't introduced to the line, and inspectors gave some instructions and left at around 2:45 p.m. Con Ed said inspectors didn't smell any gas.
De Blasio: Someone May Have 'Inappropriately' Tapped Gas Line Before East Village Explosion
But at around 3 p.m. Thursday, the sushi restaurant owner did smell gas and called the landlord, who then called a general contractor, Chief of Detectives Robert Boyce said. No one called 911, however, de Blasio said.
The contractor, Dilber Kukic, and the owner's son went into the basement and opened a door, and then the explosion happened, burning both their faces, Boyce said.
Twenty-two people were injured, four critically, after the powerful blast and fire sent flames soaring and debris flying Thursday afternoon.
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Authorities are searching for at least two people who are unaccounted for: diner Nicholas Figueroa, who had been on date at the destroyed Sushi Park restaurant, and Moises Locon, a worker there.
Firefighters using high-powered water towers continued to work Friday to extinguish pockets of fire at the site which is a giant wave of crumbled brick, twisted metal and splintered wood. Rubble was still strewn across parked cars, and a menu from the sushi restaurant and other debris were scattered across the surrounding streets.
It will take days, possibly as long as a week, to clear all the debris from the area, de Blasio said.
The Medical Examiner and cadaver dogs were on the scene Friday night in case any remains are recovered, CBS2's Matt Kozar reported.
Police earlier were trying to determine whether six other people reported missing were connected to the explosion. Boyce said they have now narrowed that list to one.
"You rarely see a scene of such devastation in the middle of a city like this," de Blasio said. "This was 24 hours ago a vibrant, bustling street and today people are dealing with the aftermath of this tragedy."
De Blasio praised the FDNY and other first responders for their "professionalism, bravery and courage" during the "complex and dangerous situation," which left six members of the fire department injured.
"We are blessed by the finest first responders anywhere in the world; this is absolutely extraordinary what our first responders did here, it should be a cause for comfort in the midst of this pain," de Blasio said. "This city knows how to handle adversity, we never welcome it, we know it will come, but we know how to handle it."
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Firefighter Michael Shepherd was off-duty when he heard and saw the blast. He quickly ran toward the scene and called up to a woman on the third-floor fire escape who was trying to get down.
"Trying to explain to her, you have to bend with your legs and lift it up and she was panicking and she couldn't do it. I had to calm her down," he said.
After she came down, he climbed up and went window by window, floor by floor, looking for anyone who might have been injured.
Earlier Friday, the mayor and other officials stepped across glass and pools of water from fire hoses as they surveyed the damage and thanked firefighters.
Some residents Friday morning saw the destruction up close for the first time.
"It's just absolutely devastating," one resident told CBS2's Andrea Grymes. "Very personal and tragic."
"It's sad," said witness Martin Thomas. "I can't even describe how sad it is."
"I'm totally devastated,'' nearby resident Naomi Machado said. "For my neighbors, for our neighborhood. We all look out for one another.''
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The blast caused three five-story buildings to collapse within a few hours of each other. A fourth, seven-story building, suffered extensive fire damage. Passers-by were hit by debris and flying glass, and bloodied victims were aided as they sat on sidewalks and lay on the ground.
"There was a loud explosion that shook the whole block, windows shook and when we walked out to look and investigate the whole building on Second Avenue and 7th was blown out," said Brandon Boudwin, who works at nearby Anthony Aiden Opticians.
"It was very quick; it was very instantaneous – kaboom," another witness said.
"The debris was on the corner, the whole thing blew," said another woman.
Meanwhile, Kukic -- who's facing unrelated charges of bribing an undercover investigator posing as a housing inspector -- was treated and released from a hospital, said his lawyer, Mark Bederow.
"His thoughts are with the people who are injured and the victims of this,'' Bederow said Friday.
Kukic declined through his lawyer to comment on the circumstances surrounding the explosion. City records show Kukic got a permit last June for plumbing, flooring, removing partition walls and other work at the building.
Boyce said Kukic had tried to help people escape the explosion.
Contractor Facing Unrelated Charges Tried To Help People Escape East Village Blast
"Right now, he's being very helpful," Boyce told reporters, including WCBS 880's Ginny Kosola.
Kukic is a relatively minor player in a 50-person bribery case that Manhattan District Attorney Cyrus R. Vance Jr. and other authorities unveiled last month. Kukic is accused of paying $600 in cash to try to get housing violations dismissed at two upper Manhattan properties he owned. He has pleaded not guilty.
The Red Cross has set up an emergency reception center at P.S. 63 and the library near Tompkins Square Park. The center will be open Saturday from 8 a.m. to 8 p.m., WCBS 880's Jim Smith reported.
The organization says they're helping at least 80 people, including one child.
"Whether folks' need is for two days or two weeks, we'll stand along side them during this period," said Josh Lockwood with the Red Cross.
The mayor has also started a fund to help victims of the explosion.
The blast happened a little over a year after a gas explosion in a building in East Harlem killed eight people and injured about 50.
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