An explosion reduced a large section of a Motel 6 near Seattle to rubble late Tuesday only moments after it was evacuated due to a gas leak.
Firefighters who were on scene in Bremerton, Washington, at the time were blown back nearly 20 feet, police said.
A gas company worker was critically injured by the blast and was flown by air ambulance to a hospital with second- and third-degree burns.
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A gas leak was reported shortly before 8 p.m. local time (11 p.m. ET). Motel workers and patrons were able to evacuate just prior to the blast, which happened at 8:24 p.m., authorities say.
"The shaking was bad enough that the neighbors thought a tree fell on their house," said Alice Adams, who lives three blocks away. "Both the sound and force made it almost instantly obvious that it was an explosion and not something smaller like a firework explosion or gunshot."
Local resident Beth Olson told NBC News: "It felt like a massive pressure concussion, like a bomb went off."
She added: "I was sitting on my floor, as was my upstairs neighbor … and as soon as we felt the concussion, I texted him and he called me, simultaneously. He's in the military so he was immediately concerned about that, of course.