“We are joining other retailers in asking our customers to no longer openly carry firearms into our stores other than authorized law enforcement officials,” Walgreens said in a statement posted online. The Deerfield, Ill.-based company had almost 10,000 stores across the U.S. as of a year ago, according to its website.

Following years of mass shootings that have killed thousands of people in schools, workplaces, at public events, shopping centers, churches, and almost every other corner of American life, some large companies have begun to alter their corporate policies around firearms.

Earlier this week, Walmart, which was for years among the U.S.’s biggest sellers of handguns and assault-style rifles, said it would stop selling bullets for some guns. It also said it was “respectfully requesting” shoppers not openly carry guns. Kroger, the grocery-store chain, also asked customers not to openly carry firearms.

The companies have been responding to a pressure campaign by activists seeking to change corporate policies around gun sales and open carry. A gunman at an El Paso, Texas, Walmart killed 22 people in early August and injured 24 others.

Walmart changed its firearms sales and carry policies after 11 advocacy groups banded together to create the Walmart Must Act Coalition. Shannon Watts, founder of Moms Demand, a gun control advocacy group, applauded 13 brands for their policies:

Representatives for CVS Health and Rite Aid, Walgreens’ two biggest pharmacy rivals, didn’t immediately respond to requests for comment.

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