PITTSBURGH (KDKA/AP) — A coalition of Walmart employees is calling for a nationwide walkout today after Saturday’s mass shooting at a store in El Paso, Texas.

The employees are demanding the chain stop selling firearms and ammunition in stores.

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Twenty-two people were killed over the weekend when a gunman opened fire at the store in El Paso as people were back to school shopping.

Last month, someone gunned down two people at a Walmart in Mississippi.

Also in July, a woman pulled out a gun and opened fire at the Walmart here in North Versailles. The incident was caught on surveillance video, and the woman is facing aggravated assault charges in the case.

And, in early November 2017, three customers were killed at a Walmart in Colorado in a random shooting by a lone gunman.

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The El Paso store shooting, however, was the deadliest in the company’s history, Walmart spokesman Randy Hargrove confirmed. No workers were killed but two are recovering from injuries.

The company’s policy on selling guns has not changed, at least not as a result of this latest shooting.

Walmart announced in February 2018 that it would no longer sell firearms and ammunition to people younger than 21 and also removed items resembling assault-style rifles from its website. Those moves were prompted by the mass shooting at a high school in Parkland, Florida, that killed 17 people.

In 2015, Walmart stopped selling semi-automatic weapons like the AR-15 style rifle, the type used in another mass shooting three days ago in Dayton, Ohio. The retailer also doesn’t sell large-capacity magazines, handguns (except in Alaska) or bump stocks, nor the AK-style firearm that was used by the El Paso shooter.

For more on the El Paso shooting and the planned walkout, visit CBS News at this link.

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