A firefighter was killed after a house in Virginia exploded Friday night, injuring 11 other people and scattering pieces of the home across the neighborhood, officials said.

Firefighters arrived at the home in Sterling, Va., a suburb of Washington, about 7:40 p.m., said James Williams, the assistant chief of operations for Loudoun County Fire and Rescue. That was around the same time the Sterling Volunteer Fire Company reported on social media that it had sent fire engines to the house to investigate a gas leak.

Soon after, the house exploded with firefighters inside, leaving people trapped and the area in “total devastation,” Mr. Williams said.

Aerial footage of the scene from local news media showed smoke and debris covering the area and barely any signs of the demolished house.

“There’s a debris field well into the street and into the neighboring homes,” Mr. Williams said, adding that the area remained an active scene as of about 11 p.m. Fire crews were still working at the site, where fire continued to smolder, and all firefighters were accounted for, he said.

As the fire authorities investigated the cause of the explosion, Washington Gas, the local utility company, said in a statement that it was “verifying the integrity of our system in the surrounding area.”

Nine firefighters were transported to local hospitals with injuries of varying severity, Mr. Williams said, as were two civilians. He did not identify the firefighter who had died, pending notification of his family.

“It’s a huge physical and emotional toll on everyone associated with the fire department,” he said.