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NEW YORK – Archbishop Nelson Perez of Philadelphia asked Catholics on Jan. 5 to join him in praying for all those that were affected by a duplex house fire that morning which killed at least 12 people, including eight children.

“In the name of the people of the Archdiocese of Philadelphia, I extend my deep condolences to all those in mourning,” Perez said in a statement. “Please join me in praying fervently for the happy repose of those who have died, for the speedy recovery of those who were injured, and in gratitude for the fire, police, and medical personnel responding to this tragedy. May the Lord wrap his loving mantle of mercy around them all.”

The Philadelphia Fire Department responded to “heavy fire” from the second floor of a three-story row dwelling at 869 North 23rd Street, in the city’s Fairmount neighborhood just before 6:40 a.m., according to Philadelphia Deputy Fire Commissioner Craig Murphy at a news conference. The fire took about 50 minutes to get under control.

In addition to the 12 deaths, two other occupants – one of them a child – were transported to the hospital, Murphy said, and eight people were able to self-evacuate. Murphy said the preliminary numbers indicate there were eight people that lived on the first-floor unit of the duplex, and 18 people that lived in the second and third floor unit.

“It’s terrible,” Murphy said. “I’ve been around for 35 years now and this is probably one of the worst fires that I’ve ever been to.”

The cause of the fire is under investigation by the fire marshal’s office, Murphy added, noting that it’s too early to tell where the first started and it’s not necessarily considered suspicious, “but we have all hands on deck because of the magnitude of the fire.”

“We intend on getting a cause for this fire.” Murphy said. “We plan on making sure that this tremendous loss of life did not happen in vain.”

Throughout the day questions emerged about the living conditions of the duplex. Murphy said there were four battery operated smoke detectors in the building that weren’t operational. As for the number of people in the home, Murphy noted that’s a licensing and inspection question while acknowledging that it was a “tremendous amount of people to be living in a duplex.”

Philadelphia Mayor Jim Kenney cautioned the public to consider the circumstances that could have led to that many people staying in the duplex, which is managed by the Philadelphia Housing Authority and federally funded, at the time of the fire.

“Sometimes it’s better for people to be indoors than on the street. Maybe there were people or relatives that needed to be sheltered,” Kenney said at the news conference. “We can’t make judgements on the people in the house, because sometimes people just need to be indoors.”

In opening remarks, Kenney called the fire “one of the more tragic days in our city’s history,” asking people to “please keep all of these folks, and especially the children, in your prayers.”

This story was updated with the latest death death toll provided by Philadelphia officials. 

Follow John Lavenburg on Twitter: @johnlavenburg