PHILADELPHIA (CBS) — Eight children are among the 12 people killed following a fire at two apartment units owned by the Philadelphia Housing Authority in the city’s Fairmount neighborhood Wednesday morning. The Philadelphia Fire Department arrived to heavy flames at the building on the 800 block of North 23rd Street just after 6:30 a.m.

Authorities confirm four adults and eight juveniles were killed in the tragic fire. The ages of the victims range from 2 to 33 years old.

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“It was terrible, most of, I’ve been around for 30, 35 years now and this is probably one of the worst fires I’ve ever been to,” Philadelphia Deputy Fire Commissioner Craig Murphy said during a press conference.

Murphy says the number of victims is “dynamic because there is still an ongoing recovery effort.”

Eight people evacuated the building and two additional people were transported to CHOP and Temple University Hospital.

“We’re getting multiple calls, reported people inside,” was heard on dispatch audio.

Dispatch audio and cellphone video take you into the moments the row home went up in flames. The multi-unit was home to at least 26 people.

“We got heavy fire filling the second floor, heavily smoke third floor, prepare for rescue,” was heard on dispatch audio.

From the moment they arrived, fire crews attacked this blaze aggressively.

Fire officials say there was heavy fire in the second-floor kitchen area.

Crews got the fire under control by 7:31 a.m.

Murphy says the building was divided into two apartments. The first-floor unit reportedly had eight occupants and the second and third-floor unit had 18 people living in it.

The multi-unit building had a described “odd layout,” possibly preventing a safe escape.

“Other than front door and rear entrance, because of the odd configuration of the house, all I know of is two exits,” Murphy said.

Officials say Licenses and Inspections will determine if it was OK for that many people to live inside each unit.

The home is owned by the Philadelphia Housing Authority. According to the PHA, there are seven smoke detectors and three carbon monoxide detectors in Unit A and six smoke detectors and three carbon monoxide detectors in Unit B. This makes a total of 13 smoke and six carbon monoxide detectors in the building that did not operate.

Dinesh Indala, a senior executive and vice president of operations for PHA, says inspections are done annually.

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“Most recent inspection on B unit was May 5, 2021, and at that time, we had six smoke detectors and three carbon monoxide detectors working,” Indala said. “We had to replace two batteries in two smoke detectors, all replaced. On a previous inspection, 9/28/2019, we also had to replace smoke detectors again in the same unit. On A unit, the latest inspection on 4/23 and two smoke detectors were installed and there were seven smoke detectors and three carbon monoxide detectors present and they were signed by the tenant as a part of the smoke detector response form.”

Indala says PHA was not aware that 26 people were living inside the unit.

“No, we were not,” Indala said. “We are cooperating with fire department and everyone else in the investigation right now. It’s L&I stuff. All the family hasn’t been notified yet so we don’t want to comment on who and what. The count for the number of people on that property is too high.”

The PHA does inspections annually and the last was in May 2021. Indala adds that it’s the holidays and it’s unclear if “they have people coming and visiting.”

Murphy says the fire is not considered suspicious at this time, but the Philadelphia Fire Department’s Fire Marshal’s Office is leading the investigation because of the loss of life.

As the investigation continues, an emotional Mayor Jim Kenney asked the public to reserve judgment as the city mourns an unspeakable tragedy.

“This is undoubtedly one of the most tragic days in our city,” Kenney said.

The destructive blaze is being thoroughly investigated by multiple agencies. With the fire department’s deputy commissioner saying this is one of the worst fires he’s seen in his 30-plus year career.

“We are working with the Fire Marshal’s Office, we plan and intend on getting a cause for the fire, making sure this tremendous loss of life didn’t happen in vain,” Murphy said.

ATF agents also responded to the scene to assist.

The Red Cross says it is providing emergency assistance for a family of five displaced from the first floor.

There are reports this fire may have been started by a Christmas tree. However, investigators are still going through evidence and haven’t released an official cause.

A GoFundMe has been started to help cover funeral expenses for the victims.

CBS3’s Matt Petrillo, Joe Holden, Alecia Reid and Jasmine Payoute contributed to this report.

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