Here's the list of companies that have bailed on partnerships with the NRA

  • Delta, United and North American Van Lines are among the latest companies to end their discount programs for members of the National Rifle Association.
  • Insurance companies Chubb and Metlife joined car rental company Enterprise and the First National Bank of Omaha in ending their relationships with the NRA.
  • "Customer feedback has caused us to review our relationship with the NRA," First National Bank of Omaha tells CNBC.

The list of companies terminating their partnerships with the National Rifle Association is growing as public outcry against the gun group escalates following the deadliest mass shooting at a public high school in U.S. history.

Delta and United Airlines said Saturday they will end group airfare discounts for NRA members and they were in the process of informing the gun group of this decision. Moving companies North American Van Lines and Allied Van Lines also ended their discounts with the group over the weekend.

FedEx — though refusing to end special discounts to NRA members — condemned the prevalence of assault rifles in the United States and said Monday it supports restricting them to members of the military.

"FedEx views assault rifles and large capacity magazines as an inherent potential danger to schools, workplaces, and communities when such weapons are misused. We therefore support restricting them to the military. Most important, FedEx believes urgent action is required at the local, state, and Federal level to protect schools and students from incidents such as the horrific tragedy in Florida on February 14th," FedEx said in a statement.

FedEx added Tuesday that its discounts apply only to NRA members, not the organization itself.

"The NRA is one of hundreds of organizations in our alliances/association Marketing program whose members receive discounted rates for FedEx shipping," the statement continued. "FedEx 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."

Here's a list of the firms that have discontinued their partnerships with the NRA in the wake of the shooting:

Avis Budget Group and Hertz Global Holdings cut ties Friday. First National Bank of Omaha cited a customer outcry in ending its NRA-branded Visa card with the group.

"Customer feedback has caused us to review our relationship with the NRA," First National Bank of Omaha told CNBC. "As a result, First National Bank of Omaha will not renew its contract with the National Rifle Association to issue the NRA Visa Card."

The National Rifle Association has defended itself vigorously amid the turmoil.

"Since the tragedy in Parkland, Florida, a number of companies have decided to sever their relationship with the NRA, in an effort to punish our members who are doctors, farmers, law enforcement officers, fire fighters, nurses, shop owners and school teachers that live in every American community," the NRA said in a statement. "Let it be absolutely clear. The loss of a discount will neither scare nor distract one single NRA member from our mission to stand and defend the individual freedoms that have always made America the greatest nation in the world."

Chubb said it gave notice to the NRA three months ago to discontinue its program, but made the announcement Friday. Metlife and Symantec also made their announcements Friday.

Hotel chain Wyndham Worldwide told CNBC it ended its relationship with the NRA late last year.

The outcry comes amid signs Americans' interest in gun control is not waning like it typically has in the wake of past mass shootings. Google searches for "gun control" have remained elevated a week after the Parkland, Florida, massacre.

BlackRock, the world's largest asset manager, said it was going to reach out to the publicly traded gunmakers "to understand their response" to the shooting. BlackRock indirectly owns shares in companies like American Outdoor Brands and Sturm Ruger as a provider of exchange-traded funds.

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