Story highlights Fire commissioner: Investigators expect to reach the piping and gas meters Sunday

Firefighters pull a Bible from the ashes of the blast site, where eight were killed Wednesday

Pastor of destroyed church is overcome when presented with intact Bible

A day before investigators expected to gain full access to the site of a deadly explosion that leveled two New York buildings, firefighters digging through the rubble found an intact Bible belonging to the evangelical church that once stood there.

Fire Commissioner Salvatore Cassano told reporters that by Sunday, investigators expected to reach the piping and gas meters in the basement at the scene of Wednesday's blast in East Harlem that killed eight people and injured dozens others.

Natural gas might have triggered the explosion that shook the vibrant neighborhood, federal officials said. The National Transportation Safety Board could start pressure-testing gas pipes in the area on Sunday, Cassano said.

On the third day of a grueling recovery effort from the three-story pile of rubble, firefighters early Saturday pulled a large waterlogged Bible from the ashes and ruins of the Spanish Christian Church, which occupied the basement and first floor of one of the two destroyed buildings.

"One of our members found a Bible, the original book they tell me of the founders of the church," Cassano said. "It was singed, but it meant an awful lot to the pastor because at least we have a remnant of the church. It showed the pastor they'll be rebuilding. This church is resilient."

Photos: Explosion destroys East Harlem buildings Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Rubble is seen on Friday, March 14, two days after an explosion leveled two apartment buildings in the East Harlem neighborhood of Manhattan, injuring dozens and killing at least eight people. Though authorities have said a gas leak may have triggered the explosion, Mayor Bill de Blasio told reporters Thursday that the official cause was under investigation. Hide Caption 1 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters look over what remains of a building affected by the explosion on March 14. Hide Caption 2 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – A vehicle crushed by debris from the building explosion is seen on the street. Hide Caption 3 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – An excavator removes debris on Thursday, March 13, from the site of a massive explosion. Hide Caption 4 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – People protect their faces from dust on March 13. Hide Caption 5 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Police officers stand near the site of the explosion on March 13. Hide Caption 6 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Smoke fills 116th Street as a stretcher is wheeled toward the site of the explosion on March 13. Hide Caption 7 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Heavy smoke rises from the debris on Wednesday, March 12. Hide Caption 8 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Medics put a person into an ambulance at the scene of the explosion on March 12. Hide Caption 9 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Water is sprayed on smoldering debris close to the scene of the building collapse. Hide Caption 10 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – A police officer covers his face with a mask to protect himself from the smoke. Hide Caption 11 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – New York City Mayor Bill de Blasio speaks during a news conference. "This is a tragedy of the worst kind," he said, "because there was no indication in time to save people." Hide Caption 12 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – New York firefighters battle the fire near 116th Street and Park Avenue, once the heart of the city's large Puerto Rican community. Hide Caption 13 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters work to contain the fire. The firefighters responding to a gas leak report barely missed the blast, Fire Commissioner Salvatore Cassano said: "If we were here five minutes earlier, we may have had some fatalities among firefighters." Hide Caption 14 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Rescue workers remove an injured person from the scene. Hide Caption 15 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Alecia Thomas, left, is comforted by her friend, Shivon Dollar, after Thomas' home was destroyed in the explosion. Hide Caption 16 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – De Blasio, in the blue jacket, arrives at the site of the explosion. Hide Caption 17 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – People stand behind a police line. Hide Caption 18 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters work from the roof of a building next to the site of the explosion. Hide Caption 19 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Workers inspect debris on the Metro North railroad tracks near the scene of the explosion. Hide Caption 20 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters observe rescue efforts after the explosion. Hide Caption 21 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Broken glass and debris litter the area around the scene. Hide Caption 22 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Hundreds of firefighters responded to the scene. Hide Caption 23 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Police search the debris. Hide Caption 24 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Smoke billows from the site of the explosion and collapse. Hide Caption 25 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Police create a one-block perimeter around the site. Hide Caption 26 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – People watch as rescue efforts continue after the explosion. Hide Caption 27 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – People run from the scene. Hide Caption 28 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Debris is scattered over a wide area as firefighters work to contain the fire. Hide Caption 29 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters examine the damage to one building after the explosion. Hide Caption 30 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters respond to the fire. Hide Caption 31 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters work to douse the fire. Hide Caption 32 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters work at the scene. Hide Caption 33 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Rubble from the explosion spills onto Park Avenue. Hide Caption 34 of 35 Photos: Explosion destroys East Harlem buildings Explosion destroys East Harlem buildings – Firefighters work to douse the fire. Hide Caption 35 of 35

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When firefighters presented the Spanish-language Bible to the church's 83-year-old pastor, the Rev. Thomas Perez, the pastor was overcome.

Perez, who has stood vigil with others at the blast site, was participating in a small prayer gathering with religious leaders and experienced chest pains, said the Rev. Vernon Williams, who attended the vigil.

Cassano said Perez was recovering at Lenox Hill Hospital in Manhattan's Upper East Side.

"He was overwhelmed with emotion, for sure," the fire commissioner said. "It's a very sacred thing for him."

After Perez was taken away by ambulance, Williams said, about two dozen people at the vigil prayed for him before carrying the Bible in a procession near the site.

"It was the altar Bible," Williams said. "There was no singing on the Bible at all. It was intact, with a little water damage."

The small evangelical church and Bethel Gospel Assembly lost five members in the explosion.

Though it is still possible other victims could be found, police said Saturday that only one known victim has not been publicly named.

"We've recovered all the people that were reported missing, but we're still looking through the debris and a couple of areas in the back in case somebody was there, Cassano said.

The ordinary rhythms of the vibrant East Harlem neighborhood of corner bodegas, botanicas, churches, shops and redbrick tenements were shattered with the Wednesday morning blast.

Said Cassano, "We're doing our best to get through as much of the debris as we can as quickly as possible and try to bring some normalcy back to the neighborhood."