The good news: It’s a Home Depot story that doesn’t involve your credit or debit card information being stolen. The not-so-good news: More than a dozen people at a California Home Depot had to be treated after a customer decided that it would be a good idea to use pepper spray on another customer.

According to KTLA-TV, four people were hospitalized and another dozen were treated by emergency responders following an incident inside a Covina, CA, Depot on Monday.

It’s unclear exactly what happened, but two men inside the store — who apparently had some sort of previous business arrangement with each other — began arguing and one of them let loose with the pepper spray.

He claims he was defending himself, and maybe that’s the case. What’s known for sure is that people were having trouble breathing, the store was evacuated, 9-1-1 responders in hazmat suits showed up, and the pepper-sprayer was arrested on charges of suspicion of unlawful possession and use of a tear gas weapon.

The man was allegedly carrying an illegally large amount of pepper spray on him, which may explain why it was able to spread throughout the store and affect so many people.

The store was reopened about two hours after authorities were first called to the scene.

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