Firefighter Trevor Brown, 45, died on Friday in a “catastrophic” house explosion that also injured 11 other first responders and two civilians in Sterling, a city about 120 miles north of Richmond, according to a statement from Loudoun County Fire and Rescue.

After receiving a 911 call from a resident about a gassy odor, the crew arrived at the house on Friday night and discovered a 500-gallon underground propane tank and a leak on the side of the residence.

“A short time later, units on scene reported a catastrophic explosion concurrent with multiple maydays from firefighters inside the residence,” Loudoun County Fire and Rescue said in the statement.

“Upon receiving the multiple maydays and calls for help, fire and rescue crews worked to locate and rescue the trapped members from the debris that covered them,” the statement continued.

After the additional responders from Loudoun and Fairfax counties were rushed in to assist, 11 first responders with varying degrees of injuries and two civilians with non-life-threatening injuries were taken to local hospitals for treatment. Four remain hospitalized as of Saturday morning, the statement said.

Brown was part of the Sterling Volunteer Fire Company and had been with the Loudoun County Combined Fire and Rescue System since 2016.

“Please keep Firefighter Brown’s family, friends and colleagues in your thoughts and prayers during this difficult time, and we ask that the family’s privacy be respected,” Loudoun County Fire and Rescue added.

The local fire marshal’s office continues to investigate the origin and cause of the explosion and has assured local residents that “this is believed to be an isolated incident and there is no ongoing danger to the community.”

Firefighters were inside when the home exploded, Fire and Rescue Assistant Chief of Operations James Williams previously said.

“Total devastation,” is how Williams described the scene and damage. “There’s a debris field well into the street and into the neighboring homes.”

Officials initially said nine firefighters suffered injuries that ranged from serious to less severe. Loudoun County Fire said Saturday that at least 10 people had been injured, including two occupants of the home who suffered minor injuries.

The occupants and their pets were removed from the residence by firefighters, officials said. Four first responders remain in the hospital.

“Please keep Firefighter Brown’s family, friends, and colleagues in your thoughts and prayers during this difficult time, and we ask that the family’s privacy be respected,” Loudoun County Fire and Rescue said in a post on X.

Johnson said they have not yet determined a “complete cause” of the explosion.

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