PHOENIX (AP) – Gun store owners in states on the U.S.-Mexico border are suing the acting director of the Bureau of Alcohol, Tobacco, Firearms and Explosives. At issue is a new requirement that owners alert federal authorities if someone buys multiple high-powered rifles over five days.

The new requirement is only for gun stores in the four states that border Mexico: Texas, California, Arizona and New Mexico.

It goes into effect August 14 and stems from a law enforcement operation in Arizona that resulted in high-powered weapons flowing into Mexico.

The gun store owners argue that the requirement is unlawful, would hurt them economically and invades the privacy of their customers.

The lawsuits were filed in Texas, Washington, D.C. and New Mexico on Wednesday and Thursday. The National Rifle Association is funding them.

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