(STERLING, Va.) — A firefighter was killed and 10 others injured when a house in Virginia exploded while they were responding to a gas leak, authorities said.

Firefighters responded to the home in Sterling around 7:48 p.m. Friday after a resident reported smelling gas, according to Keith Johnson, chief of the Combined Fire & Rescue System in Loudoun County.

A 500-gallon underground propane tank on the side of the house was leaking gas into the home, he said.

Nearly 40 minutes after arriving at the scene, there was a “catastrophic explosion” while firefighters were inside the house working the emergency, Johnson said.

“That was somewhat chaotic as we tried to figure out how many firefighters were trapped under the debris,” Johnson said at a press briefing on Saturday.

A volunteer firefighter was pronounced dead at the scene. He was identified as Trevor Brown, 45, with the Sterling Volunteer Fire Company.

He had been with the company since 2016 and is survived by a wife and three children, the fire company said.

“We lost a family member,” Johnson said.

The fallen firefighter from last night’s home explosion in Sterling has been identified as Firefighter Trevor Brown, 45, of the Sterling Volunteer Fire Company. He has been affiliated with the LC-CFRS since 2016. @Chief600KJ pic.twitter.com/1olm23ySdX

— 𝑳𝒐𝒖𝒅𝒐𝒖𝒏 𝑭𝒊𝒓𝒆 𝑹𝒆𝒔𝒄𝒖𝒆 (@LoudounFire) February 17, 2024

Ten firefighters were transported to local hospitals, including to the Washington Burn Center in D.C., Johnson said. Four firefighters remain hospitalized with varying levels of injury and are expected to survive, he said.

The two occupants of the home and several pets had been evacuated, Johnson said. The two residents had minor injuries and have been treated and released, he said.

The exact cause of the explosion remains under investigation.

“We can assume it was propane related but no complete cause has been initiated,” Johnson said.

The investigation will also seek to determine how the leak occurred and how the gas got into the home.

The Loudoun Sheriff’s Office and the Bureau of Alcohol, Tobacco, Firearms and Explosives are aiding in the investigation, according to Loudoun Fire-Rescue Assistant Chief James Williams.

The large debris field stretched into the street and into the vicinity of neighboring homes. The house that exploded is destroyed, the assistant chief said.

“This is the worst call that we can respond to,” Williams said.

The chief said he is proud of the firefighters’ response and credited it with limiting the number of fatalities in the incident.

“Our folks did their job, they showed up and they did what they had to do,” he said. “We prepare for this. We have a full plan for dealing with line-of-duty deaths. We hope you never have to use it but we’re using it today.”

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