AURORA, Colo. (CBS4) – Crews rescued a large number of cats from inside an apartment in Aurora on Thursday.

Aurora code enforcers were responding to a water leak on Walden Road near Buckley Air Force Base. When they arrived the smell of ammonia was so intense that the unit had to be sealed.

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Neighbors said they could smell the run-down unit through their walls.

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“It was unbearable. I would come in and it was all in my closet. All in my bathroom (had) the smell. I would walk in and it was like a mask hit me,” Delmar Mulwee said.

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An animal recovery team was called to the scene and they said they couldn’t even go inside the apartment without wearing respirators.