FedEx Corp. is maintaining discounts for members of the National Rifle Association, even as calls for a boycott mount on social media after a deadly school shooting in Florida.

The courier said it “has never set or changed rates for any of our millions of customers around the world in response to their politics, beliefs or positions on issues.” The NRA is one of hundreds of organizations in its alliance programs, FedEx said Monday in its first public comment on the matter.

Since Sunday, the #BoycottFedEx hashtag has been included in more than 700 posts on Twitter, including one by Marjory Stoneman Douglas high school student David Hogg that has been shared more than 13,000 times. Hogg—who now has more than 330,000 followers on Twitter—and peers at Stoneman Douglas have gained national attention as advocates for gun-law reforms since a Feb. 14 attack at the school left 17 students and teachers dead.

FedEx said its views on firearms policy differ from the NRA’s. While the company said it supports the constitutional right of U.S. citizens to own firearms, subject to appropriate background checks, it supports keeping assault rifles out of civilian hands.

‘Inherent Danger’

Assault rifles and large capacity magazines are “an inherent danger to schools, workplaces and communities when such weapons are misused,” FedEx said in the statement. “We therefore support restricting them to the military.”

Shares of the Memphis, Tennessee-based company rose less than 1 percent to $254.51 at the close in New York. They were unchanged in late trading, following the company’s statement on the NRA.

FedEx is part of the NRA Business Alliance and offers discounts through its FedEx Advantage program for shipping by FedEx Ground and FedEx Express and some services at FedEx Office, according to company and NRA websites. NRA officials also didn’t immediately respond to a request for comment.

Delta Air Lines Inc. and United Continental Holdings Inc. are among companies that cut ties with the NRA following online calls to boycott the gun lobbying group. Symantec Corp., owner of Lifelock and Simplisafe Inc.; rental car companies Hertz Global Holdings Inc. and Avis Budget Group Inc. and insurer MetLife Inc. all have cut ties to the NRA. Apple Inc. and Amazon.com Inc. were among companies being pressured Monday on social media to drop the lobbying group’s streaming TV channel.

Supporters of the NRA, however, were mounting their own campaigns. Georgia Lieutenant Governor Casey Cagle, a Republican who is running for governor, on Monday threatened to kill tax legislation that would benefit Delta unless it reinstates its relationship with the NRA. A bill before the state’s General Assembly would exempt jet fuel from sales tax, benefiting the airline.

“Corporations cannot attack conservatives and expect us not to fight back,” Cagle wrote on Twitter.

Delta said Saturday it would end an NRA contract for discounted rates on flights to the group’s annual meeting. The airline also asked to have its name removed from the NRA’s meeting website.