Shares of Kroger (KR Quick QuoteKR - Free Report) gained as much as 2.5% in morning trading Thursday after the grocery giant announced that it would stop selling firearms to customers under age 21 at its Fred Meyer stores, following a trend of retailers changing gun sales rules in the wake of mass shootings.

“Recent events demonstrate the need for additional action on the part of responsible gun retailers,” the company said in a statement. “We believe these are common sense steps we can take immediately that are in line with our values and our vision.”

Retail behemoth Walmart (WMT Quick QuoteWMT - Free Report) made a similar announcement on Wednesday, while Dick's Sporting Goods (DKS Quick QuoteDKS - Free Report) said that it will discontinue the sale of assault-style rifles at its Field & Stream stores. Dick's is also set to stop selling high-capacity magazines.

Kroger shares climbed more than 2.5% higher to touch an intraday high of $27.85 on Thursday morning. Walmart shares are down about 2% since it made its own announcement. Dick's has moved about 1.2% higher since its decision.

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