Hey, everyone. I'm Em Wyn with ABC News here in Sterling, Virginia. This is what's leftover of the home that exploded late last night. What we understand is that firefighters were called to this house because of the smell of gas. They entered the home and went down into the basement. And what we understand is that they found a 500-gallon propane tank underground that had a leak. Now, what I've heard from neighbors is the impact of the explosion rattled these homes. Some tell me they thought lightning had struck their house. You can see debris has now been scattered across many of the neighbor's homes. Insulation, we can see pieces of the homes still scattered across some of the foundation, and some of these pieces are also still stuck in the trees on that property. The latest update we know is one firefighter has died. His name is Trevor Brown. He was 45 years old. He was married, and he was a father of three. Ten other firefighters were taken to the hospital. Tonight, we understand that four of them are still in the hospital recovering. Two civilians, which we've heard were the ones who were living in this home, were also sent to the hospital, and they are expected to be okay.

Some people in the neighborhood have left some flowers in the wake of Brown's death. The origin of this catastrophic explosion is still under investigation.