Dick’s Sporting Goods Inc. said it has stopped selling assault-style rifles at all its stores and would no longer sell guns to those under 21 years of age, in the latest corporate response after a gunman killed 17 people at a Florida high school two weeks ago.

The Pittsburgh-based company, with about 800 stores, previously had ended the sales of assault-style rifles at its flagship Dick’s stores after the 2012 elementary school shootings in Newtown, Conn. It still sold them at its 35 Field & Stream stores.

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