Dick's Sporting Goods officials said the chain is suspending sales of modern rifles nationwide because of the school shooting in Connecticut.
Dick's also said it's removing all guns from display at its store closest to Newtown, where the massacre took place.
Authorities said a gunman killed 26 people, mostly children, with a military-style rifle at Sandy Hook Elementary on Friday. He then killed himself.
A statement posted on Dick's corporate website expresses sympathy for the victims' families. It said sales of modern sporting rifles will be suspended during "this time of national mourning."
It's not clear how long the suspension will last.
“It’s a good idea. It should have happened before this,” Dick’s shopper Andy Zahren said.
Pittsburgh-based Dick's operates more than 500 sporting-goods stores in 44 states.
Walmart has also made changes following Friday’s shooting. It pulled a certain type of Bushmaster rifle, one believed to be similar to one the gunman used, from its online store.
The following is the entire statement released by Dick’s Sporting Goods: “We are extremely saddened by the unspeakable tragedy that occurred last week in Newtown, CT, and our hearts go out to the victims and their families, and to the entire community.
“Out of respect for the victims and their families, during this time of national mourning we have removed all guns from sale and from display in our store nearest to Newtown and suspended the sale of modern sporting rifles in all of our stores chainwide.
“We continue to extend our deepest sympathies to those affected by this terrible tragedy.”