Firefighters found the kitten cowering under a burned couch, according to owner Nicole Villanueva. She told 9NEWS that little "Eleven" was in her apartment - on the top floor of a nearby building.

"[Firefighters] said my windows melted, but I have my cat so I don't care," she said with a laugh.

Villanueva said her unit was on the corner of her building and as close to the blaze that destroyed a construction site and took at least one life.

The fire broke out just after noon, quickly engulfing the construction site near 18th Avenue and Emerson Street. It sent a plume of smoke 200 feet into the air and the heat from the blaze could be felt 400 feet away. It sent embers all over Capitol Hill - some found as far away as the state Capitol building.

One person died in the blaze and another is still unaccounted for, fire authorities said.

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Over 100 firefighters responded and got the blaze under control. The fires spread to five nearby buildings, including Villanueva's. She told 9NEWS firefighters said her roof was on fire.

Her cat is named after the Stranger Things character, Eleven, and was at first a feral cat before Villanueva rescued her.

"She was feral, but kind of like El had a rough start to life - my kitten is starting to bloom too," she said. "So she's getting super social. Today was kind of a hard day for her, so she's shaking."

She said that firefighters found little Eleven cowering under her burned couch. She joked she'd have to find her a new home.

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"My apartment was actually in the corner, so it was as close as my building could get to the fire and it was also a top apartment so I guess my roof caught fire but at least I have her," she said.

She thanked the firefighters for saving Eleven. She said that as soon as firefighters got the situation under control, they took her keys and went to save her cat.

"It means so much," she said.

The reunion was captured on 9NEWS at 4 p.m. - 9NEWS reporter Anastasiya Bolton pointed it out while explaining the damage from the fire.