Three people were killed and at least five others were hospitalized when a gas explosion destroyed a Dallas apartment complex Thursday afternoon, city officials said.

The blaze erupted just before 1 p.m. in the Oak Cliff neighborhood, according to Dallas Fire-Rescue and the Dallas Police Department.

Dallas Fire-Rescue said that the incident was deemed a two-alarm fire when crews responded to a call about a gas leak but that it escalated into a five-alarm fire.

“Our first responders, while they were en route to that gas leak, a subsequent explosion occurred,” Deputy Chief Mark D. Berry said at an evening news conference. Officials have said that firefighters were at the scene within two minutes of the call.

Three bodies were found in the debris of the complex. They were identified as two females and one child, said Jason Evans, a Dallas Fire-Rescue spokesperson, in an evening update. Two were found in one unit and one in another, Dallas Fire-Rescue Chief Justin Ball said Friday.

Five others were hospitalized, he said.

Three were transported to hospitals, one of whom is in critical but stable condition. The other two have been released or will be by night’s end, Evans said.

Two other people self-transported to the hospital, both with minor, non-life-threatening issues, which have been addressed, he said.

Out of the 22 units at the complex, 19 were occupied by families and “to the best of our knowledge, everyone is accounted for,” Ball said Friday.

The operation has moved from rescue to recovery mode shortly after the blaze.

“We will continue searching the building through the excavation process and overnight until every last foot, inch of that property has been searched,” Evans said.

He became emotional as he described the scene.

“We pulled up on the scene to see a building completely destroyed like that,” he said. “ ... There are a number of things that we are before we are first responders, we’re parents. And with school being let out and the possibilities regarding who might be in those apartments, they really weigh on the heart.”

Video showed the walls of the complex blanketed with ash and the roof collapsed amid the remains of the structure.

A contractor was working at the building Thursday and struck a gas line, which led to the explosion, NBC DFW reported.

Dr. Gus Concarley, the director of Dallas’ Department of Transportation Public Works, said Thursday the city had no active work in that area.

“The fire is contained, but our members are still working on the scene to do primary searches,” Assistant Fire Chief James Russ said at an earlier news conference.

Atmos Energy, a natural gas distributor that serves multiple states, including Texas, said the fire department notified it at 12:51 p.m. that “a construction crew unrelated to Atmos Energy damaged a natural gas pipeline near 409 E. 9th Street.”

Atmos said that its technicians are working with first responders and that natural gas service in the immediate area is off.

Mayor Eric Johnson said at the news conference: “I want to encourage our entire city, this entire state, the entire nation to come together and pray for all the people, all the families who are affected by this tragedy we are experiencing here today in our city.”

The National Transportation Safety Board said it is sending a team to Dallas to investigate the explosion alongside the Dallas Fire-Rescue’s arson division.