Rescuers are scouring the wreckage of a Dallas apartment building for any additional victims after a massive explosion and fire killed at least three people, including a child.

The blast occurred Thursday afternoon as firefighters were rushing to investigate a reported gas leak.

The powerful explosion shook nearby homes and quickly engulfed the two-story complex in Dallas’s Oak Cliff neighborhood, south of downtown. A towering plume of black smoke was visible for miles after the explosion.

In addition to the three fatalities, at least five people were injured and taken to hospitals, according to Dallas Fire-Rescue spokesperson Jason Evans. The exact number of residents in the destroyed complex remains unclear.

By Friday morning, several blocks surrounding the explosion site remained sealed off by police cars and tape. Law enforcement officials and workers in bright yellow vests could be seen sifting through the rubble of what was once the apartment building.

The acrid odor of the fire still hung over the area as investigators searched through the charred wreckage. A security perimeter was maintained, with several fire trucks and police vehicles still present.

The National Transportation Safety Board is deploying a team to investigate the incident, which falls under its purview for gas pipeline accidents.

Dallas Fire-Rescue Deputy Chief Mark Berry confirmed that firefighters were responding to a gas leak call when the explosion erupted.

“We had the cavalry coming,” Berry said. “But the explosion had already taken place.”

Evans did not rule out that more victims could be found as crews sifted through the charred remains of the building, noting that by late Thursday, less than half of the scene had been searched by hand, with some areas requiring excavation.

Atmos Energy, a natural gas provider, stated that fire officials informed them a construction crew, unrelated to the company, had damaged a pipeline near the site. Natural gas service to the area has been shut off, and Atmos Energy is cooperating with investigators on-site.

Sherry Woods, who lives across an alleyway from the fire site, recounted smelling what she and her boyfriend believed to be gas moments before the blast.

“All you heard was ‘boom.’ I shook like something was hitting me. It was scary to hear something like that. I felt the building shake,” Woods said.

A family reunification center was established at a nearby high school. Several hours after the blaze, Frances Rizo was still desperately trying to reach a friend who lived in the building, lamenting, “She’s not answering her phone.”

Trish Thompson, a nearby resident, surveyed the devastation Friday morning, noting the void where the complex once stood just 24 hours earlier. She recalled hearing a “loud rumble, something more like a train to me” followed by smoke and fire.

“Pray for them,” Thompson urged.