An employee at a Houston-area PetSmart has been fired, the company said, after a viral video captured her “unacceptable” treatment of a Shih Tzu during a grooming session.

The incident took place Thursday and was witnessed by two customers who happened to be walking by the grooming section of a PetSmart in Katy, a suburban city west of Houston.

Terah Leder said the treatment of the dog was so egregious, she had to record it on her cellphone through the window.

“She was just being very aggressive with that little dog, just grabbing it by the ears,” Leder told The Washington Post, referring to the female groomer. “It was just unnecessary. The small dog was not really being aggressive or even being resistant, really.”

In Leder’s video, the groomer can be seen gripping a Shih Tzu’s muzzle and jerking its face several times while trying to trim the fur around the dog’s neck. At one point in the video, the groomer lets go of the dog’s face but then yanks its right ear to force the dog’s head into a different angle.

After that, Leder and her friend can be heard banging on the windows and cursing about how the dog was being treated.

“I kept banging on the window from where I was,” Leder said. “[The groomer] looked at me right in my eyes and I worded with my lips ‘I saw you.’ ”

Leder said she reported it to the store’s managers and was given a number for PetSmart’s corporate offices. She called to complain there as well — but said the grooming was allowed to continue.

Zahiana Jenkins, who also observed the grooming with Leder, said they were “flooded with anger” and waited at the PetSmart for an hour for the dog’s owner to show up.

“It came to the point where it wouldn’t have felt right to leave without finding the owner and letting her know what happened to her sweet baby because the [PetSmart staff] did not and wouldn’t have let her know what happened,” Jenkins wrote on Facebook.

When Brooke Vowers finally arrived to pick up her Shih Tzu — a 2-year-old named Boo — she said she was surprised to find the women waiting for her with the video and even more alarmed at its content.

“That was just a tidbit of the video, so I’d hate to think what happened in four hours,” Vowers told KTRK News. “The fact that that could happen to anyone else’s dog is just concerning to me.”

Vowers posted the video to her Facebook page Thursday, where it has since been viewed nearly half a million times. (Note: The video includes a warning for potential “graphic violence or gore” and also contains profanity.) Thousands of commenters echoed Vowers’s shock and concern over what they saw.

“i am sick to my stomach about it and will not be going back !!!!!!!!!” Vowers wrote.

The groomer was fired after the video surfaced, the company said.

“This treatment is completely unacceptable and will not be tolerated,” a PetSmart spokeswoman said in an email Saturday. “The associate was immediately terminated. At PetSmart, we all love pets, and this video does not represent who we are as a company.”

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