NEW YORK (CBSNewYork/CBS News/AP) — The National Rifle Association faced a growing backlash Sunday as companies cut ties to the gun industry following the Valentine’s Day massacre at a high school in south Florida.

The latest companies to end their ties with the NRA were Delta and United Airlines, two of the three largest U.S.-based airlines.

Corporate ties to the NRA aren’t the only elements undergoing scrutiny after a shooting at Marjory Stoneman Douglas High School in Parkland, Florida, that left 17 dead on Valentine’s Day. Broward County Sheriff Scott Israel said he’s investigating claims that some Coral Springs police officers saw several of his deputies outside the building after the shooting began.

On Thursday, Scot Peterson, the school’s resource officer, resigned under fire from the sheriff’s office for failing to enter the building where police say former 19-year-old student Nikolas Cruz was gunning down students with an AR-15 assault-style rifle.

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Here is a list of some of the companies that have cut ties or distanced themselves from the NRA:

  • First National Bank of Omaha: The bank announced that it would not renew a co-branded Visa credit-card with the NRA.
  • The Hertz Corp.: The rental car company ended its discount program for NRA members.
  • MetLife Inc.: The insurer terminated discounts that had been offered to NRA members on the NRA website
  • Enterprise Holdings Inc.: The car rental company that also owns Alamo and National cut off discounts for NRA members.
  • Symantec Corp.: The software company that makes Norton Antivirus technology ended its discount program with the NRA.
  • Chubb Ltd.: The insurer announced it was ending participation in the NRA’s gun-owner insurance program, though it provided notice three months ago.
  • Best Western: The hotel chain told multiple social media users that it was no longer affiliated with the NRA, though it did not say when that decision was made.
  • Wyndham Hotels: The hotel chain told social media users it is no longer affiliated with the NRA without specifying when that decision was made.
  • United Airlines: United said in a tweet Saturday it is “is notifying the NRA that we will no longer offer a discounted rate to their annual meeting and we are asking that the NRA remove our information from their website.”
  • Delta: “Delta is reaching out to the NRA to let them know we will be ending their contract for discounted rates through our group travel program,” the company tweeted Saturday. “We will be requesting that the NRA remove our information from their website.”
  • Avis and Budget Rental Car: The companies said they will no longer provide NRA member discounts, effective March 26.
  • TrueCar: The automotive pricing website said on Twitter that it would end its relationship with the NRA on February 28.

The moves have come as petitions circulated online targeting companies offering discounts to NRA members on its website. #BoycottNRA was trending on Twitter.

In a statement Saturday, the NRA condemned companies who severed ties with the organization.

“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, firefighters, nurses, shop owners and school teachers that live in every American community.  We are men and women who represent every American ethnic group, every one of the world’s religions and every form of political commitment,” it said Saturday.

It continued, “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.”

The State of Florida also was facing some backlash. One of the survivors of the Florida school shooting suggested Saturday on Twitter that tourists stay away from the state. He got an immediate response.

“Let’s make a deal,” tweeted David Hogg, a Stoneman Douglas student who has been a major player in the #neveragain movement. “DO NOT come to Florida for spring break unless gun legislation is passed.”

Wendy Glaab, 60, of Fonthill, Ontario, Canada, was among the first to respond. “I like many Canadians travel to Florida from time to time to escape our winter. I can’t speak for others but I will not be returning until meaningful gun control legislation is in place.”

Glaab told The Associated Press on Saturday that her sister owns property in Fort Lauderdale and she is able to visit any time she chooses.

Members of the NRA have access to special offers from partner companies on its website, ranging from life insurance to wine clubs. But the insurance company MetLife Inc. discontinued its discount program with the NRA on Friday. Symantec Corp., the software company that makes Norton Antivirus technology, did the same. Insurer Chubb Ltd. said it is ending participation in the NRA’s gun-owner insurance program, but it provided notice three months ago. The program that provided coverage for people involved in gun-related incidents or accidents had been under scrutiny by regulators over marketing issues.

Car rental company Enterprise Holdings, which also owns Alamo and National, said it was cutting off discounts for NRA member, as did Hertz.

Other companies, including Wyndham Hotels and Best Western hotels, have let social media users know they are no longer affiliated with the NRA, though they did not make clear when the partnerships ended.

The swiftness of the corporate reaction against the NRA has differed from that of past shootings, including the 2012 Sandy Hook Elementary School massacre that claimed 26 lives, and the killing of 58 people in Las Vegas last fall, said Bob Spitzer, a political scientist at SUNY Cortland and a scholar on gun politics. Spitzer said the reaction was likely a reaction to the student mobilization that followed the Florida shooting, but he said it was too soon tell how significantly it will sway the country’s wider gun debate.

NRA Executive Vice President Wayne LaPierre said this week at the Conservative Political Action Conference that those advocating for stricter gun control are exploiting the Florida shooting.

President Donald Trump has aligned himself with the NRA, suggesting some teachers could be armed so that they could fire on any attacker. However, Trump has also called for raising the minimum age for purchasing semi-automatic rifles, a move the NRA opposes.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)