LEWISVILLE, Texas (AP) — An explosion Friday in a North Texas neighborhood leveled a home that is part of a nonprofit group's affordable housing program, injuring three men and scattering debris.

Authorities were still trying to determine what caused the blast inside the home in Lewisville, about 20 miles northwest of Dallas. Two firefighters who were standing on the street near the home and another man who was inside were injured.

Lewisville Assistant Fire Chief Brian Freed said crews will search the debris, but officials believe they've accounted for everyone who might have been in the duplex. The injured man is believed to live alone, based on what neighbors told firefighters, Freed said.

Firefighters had waited to search the debris until a natural gas line near the home was shut down.

The injured men were taken to Medical Center of Lewisville. Freed said the man who lived in the home was in intensive care after surgery. One of the firefighters was hospitalized with chest pains but was expected to recover. The other firefighter had been treated and released. None of the men were immediately identified.

The home is owned by Christian Community Action, which rents it out to families who are struggling financially, said Ron Batts, president and CEO of the nonprofit group.

Freed said firefighters had first gone to the home around 10 a.m. Friday after a gas leak was reported. Natural gas provider Atmos Energy worked on the leak for about 2½ hours when the home, which was next to the line being worked on, exploded.

"There was no indication. It was just an immediate explosion," Freed said. Some homes in the area had been evacuated when the leak was first reported, he said.

Freed said construction work originally caused the leak.

Jennifer Ryan, a spokeswoman for Atmos Energy, said a third party construction crew had damaged the natural gas line while working on a utility pole.

"Crews are working diligently to make repairs to the line, restore service and make sure the area is safe," Ryan said. Continued...