Greg Conn captured the incident that took place at the Superpumper in Phoenix on his cellphone.
Conn told KPHO he started recording as the woman started arguing with a couple at the counter.
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"The lady went off on her," said Conn. "Told the cashier not to serve her and that she could go back to her country."
Surveillance video shows the woman pointing her finger and even pushing a man on his shoulder while his hands remained in his pockets.
The argument then escalated and the woman could be heard saying: "You're going back to Mexico."
That's when she shoves the other woman and the woman slaps her back in the face.
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The video has been shared thousands of times.
"All I can tell you is that my wife has been going through a mental crisis," said Bob Harrian.
Harrian said his wife is now undergoing an intervention.
"I love her dearly and that's not who she is, and I just want everyone to know how sorry I am and the lady that altercation. I am so sorry, I don't know her name. I don't know how to reach her, I just want to share [that] I'm so sorry all that happened," said Harrian.
Superpump said it has banned the woman from all 13 Arizona stores.
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