A 20-year-old Oregon man has accused Walmart and Dick's Sporting Goods of age-discrimination for refusing to sell him a rifle.

Tyler Watson filed Oregon county court lawsuits against the retailers on Monday, six days after they announced they would not sell guns to buyers under 21.The companies added the higher age restriction after the massacre at Marjory Stoneman Douglas High School in Parkland, Fla.

Oregon law allows state residents to buy shotguns or rifles as of age 18. Federal law also allows people 18 and older to buy rifles or shotguns from licensed dealers.

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Watson's lawsuits may be the first of their kind in the U.S., his attorney, Max Whittington, told The Oregonian/Oregon Live , media outlets that first reported the cases on Monday.

Watson went to a Field and Stream store owned by Dick's Sporting Goods in Medford, Oregon on Feb. 24 "for the purpose of buying a .22 caliber Ruger 10/22 rifle," according to the lawsuit filed in state Circuit Court for Jackson County.

He left after being told the store would not sell him any firearm, including rifles, shotguns or ammunition for the weapons, unless he was 21, the lawsuit alleged. The refusal came four days before the retail chain publicly announced its new sales policy for firearms.

Watson encountered a similar scenario when he went to a Walmart store in Grants Pass, Oregon on March 3 "for the purpose of buying a rifle," according to the separate lawsuit filed in state Circuit Court for Josephine County.

Watson did not know about the new age policy for gun sales when he went to the Field and Stream store, Whittington told The Oregonian/Oregon Live. It was not immediately clear whether Watson learned about the change before he went to the Walmart store.

"He was really just trying to buy a rifle," Whittington said of the initial purchase attempt. The attorney also said Watson was not part of any organized movement taking action against retailers that have enacted tighter restrictions on gun sales.

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The lawsuits seek legal injunctions ordering the retailers "to stop unlawfully discriminating against 18,19, and 20-year-old customers at all Oregon locations," as well as unspecified punitive damages because of "the willful nature of the discrimination."

Walmart spokesman Randy Hargrove said Tuesday that the company, one of the nation's largest gun-sellers, reviewed its policy on firearm sales in light of recent events.

"As a result, we raised the age restriction for the purchase of firearms and ammunition to 21 years of age. We stand behind our decision and plan to defend it," said Hargrove. "While we haven’t seen the complaint, we will respond as appropriate with the court."

Dick's Sporting Goods did not immediately respond to an email seeking comment.

Separately, the National Rifle Association last month criticized legislative proposals to ban people under age 21 from buying rifles or shotguns.

"Passing a law that makes it illegal for a 20- year-old to purchase a shotgun for hunting or an adult single mother from purchasing the most effective self-defense rifle on the market punishes law-abiding citizens for the evil acts of criminals," the gun rights organization said.