NEW YORK - Rescue workers using dogs and thermal-detection gear to search rubble for more victims of a gas explosion found an eighth body on Thursday while investigators tried to pinpoint the source of the leak and determine whether it had anything to do with the city's aging gas and water mains, some from the 1800s.
At least five people were unaccounted for after the deafening blast Wednesday morning destroyed two five-story East Harlem apartment buildings that were served by an 1887 cast-iron gas main. More than 60 people were injured.One of the two buildings destroyed in the explosion had installed new gas pipes last year, records show, as the utility serving the area continued to search for where gas had leaked.
The utility, Con Edison, said that it remained to be seen whether there had been a leak in a company gas main or in a customer-installed line. It said it was conducting a thorough review of records of gas pipes in the area of the blast on Park Avenue, reports CBS New York.
New York City building records do not show any work under way at either address, but one, owned by the Spanish Christian Church, had obtained permits and installed 120 feet of gas pipe last June.
It is still not clear whether a ruptured pipe or something else caused the explosion.
A Con Edison spokesman, Bob McGee, said Thursday that methane-detection trucks found nothing amiss in the neighborhood on Feb. 28 and Feb. 10.
McGee said the mobile surveys were done periodically, especially when there were extreme temperature fluctuations, salt on the street or other factors that might affect the underground infrastructure.
The fiery blast erupted at about 9:30 a.m. Wednesday on Park Avenue and 116th Street, about 15 minutes after a neighborhood resident reported smelling gas, authorities said.
Con Edison said it immediately sent workers to check out the report, but they did not arrive until it was too late.
Many in the neighborhood have said that they had previously smelled a gas odor in the area and some said that they had reported it to 311, the city hotline.
"I smelled gas Tuesday night when we left prayer but not in the building so I went into the 116th deli and told them, 'Check it out because it may be from you,'" said Carmen Vargas Rosa, a member of the church on the ground floor.
A tenant in one of the destroyed buildings, Ruben Borrero, said residents had complained to the landlord about smelling gas as recently as Tuesday.
A few weeks ago, Borrero said, city fire officials were called about the odor, which he said was so bad that a tenant on the top floor broke open the door to the roof for ventilation.
"It was unbearable," said Borrero, who lived in a second-floor apartment with his mother and sister, who were away at the time of the explosion. "You walk in the front door and you want to turn around and walk directly out."
Edward Foppiano, a Con Ed senior vice president, said there was only one gas odor complaint on record with the utility from either address, and it was last May, at the building next door to Borrero's. A small leak in customer piping was fixed, he said.
The block was last checked on Feb. 28 as part of a regular leak survey, and no problems were detected, Foppiano said.
Police identified four of the dead: Griselde Camacho, 45, a Hunter College security officer; Carmen Tanco, 67, a dental hygienist who took part in church-sponsored medical missions to Africa and the Caribbean; Andreas Panagopoulos, a musician; and Rosaura Hernandez, 22, a restaurant cook from Mexico.
Mexican officials said a Mexican woman, Rosaura Barrios Vazquez, 43, was among those killed.
The bodies of two unidentified men were also pulled from the rubble.
At least three of the injured were children. One, a 15-year-old boy, was reported in critical condition with burns, broken bones and internal injuries.One of the side-by-side buildings had a piano store on the first floor, the other the storefront church.
City records show that the building where Borrero lived was owned by Kaoru Muramatsu, proprietor of the piano business. A phone number listed for Muramatsu rang unanswered.
Records at the Department of Housing Preservation and Development indicate the agency responded to complaints from a tenant and cited Muramatsu in January for a broken outlet, broken plaster, bars over a fire escape, a missing window guard and missing carbon monoxide and smoke detectors.
The gas main that serves the area was made of plastic and cast iron, and the iron dated to 1887, Foppiano said.
"Age is not in and of itself an issue with cast iron," he said, noting that Con Edison has a cast iron replacement program and the pipe was not slated to be removed in the next three-year period.
A National Transportation Safety Board team arrived Wednesday to investigate. The agency investigates pipeline accidents in addition to transportation disasters.
NTSB team member Robert Sumwalt said at press conference on Thursday that because searchers were still looking for victims, the team had not been able to examine the gas pipes. Once the team is able to gain access to the site, it will conduct a pressure test of the distribution line along Park Avenue and then of service lines to the buildings to determine the source of the leak.
The main pipe is still intact, Sumwalt said, which is not unusual for a low-pressure pipe.
"This pipe is still in the ground," he said. "So there is no obvious to the eye, no apparent leak location and that's what the pressure test will be used for, to determine the location of the leak."
Asked whether the team knew that the explosion was a result of a leak in a pipe rather than from a stove or heater, he said, "No, we have not narrowed that down, but we intend to find out precisely where the gas originated. That's what we plan to do."
"We will be looking at all reports," Sumwalt said. "We'll be looking at Con Ed's call logs to see when the first calls started coming in."
Aging infrastructure - crumbling bridges, highways, water mains and gas lines - has become a major concern in recent years, especially in older cities in the Northeast, and has been blamed for explosions, floods and other accidents.
"We know this is a fundamental challenge for New York City and any older city," New York City Mayor Bill de Blasio said. But he said the federal government needed to provide more aid to cities to deal with the problem.
New York City has 1,300 miles of gas mains made of cast iron and unprotected steel that can break down over time. The cost of replacing the old pipes in New York City could be as high as $8 million a mile.
"They rust, the joints start to leak, they buckle as the ground under them erodes from water and other things," Robert Jackson of Duke University told CBS News' Michelle Miller.
Jackson studies the nation's gas distribution system, and over two months, his team detected nearly 3,500 leaks in Boston and more than 6,000 in Washington, D.C.
In a dozen of so of those cases his team found that the air in the manholes under the streets was explosive, Jackson said.
Natural gas accidents are responsible for 17 deaths and $133 million in property damage every year.