Walmart recently took a lot of heat on social media over a photo showing a back-to-school promotional sign over a gun display case. The retailer now says it has definitive proof that the sign was posted as a prank, but is not providing any additional details.

Multiple Twitter users posted the below image, which shows an “Own The School Year Like A Hero” promotional sign placed above a vertical glass display case in a Walmart store:

Aside from the sign being inappropriate, there were other indications that this display was not part of the official Walmart campaign, like the fact that there was only one back-to-school sign posted in the entire firearms section, and that this only happened at one Walmart store. But was it put there by a rogue, disgruntled employee, an impish customer, or maybe it was just a goof — a worker putting the sign down for a moment while rearranging a more appropriate section of the store?

In a statement to the Associated Press, a rep for Walmart says the company has “definite proof it was a prank.”

Beyond that, the retailer isn’t currently saying anything else about the type of proof it has, who was responsible for placing the sign on the gun case, or even where this store is located.

Last week, a woman who claimed to be the photographer insisted in an interview that the image had been snapped at a Walmart in Evansville, IN. Walmart continues to claim that this is not the case, but will not reveal what it maintains was the real site of the prank.

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