Colin Kaepernick’s protest of the national anthem apparently is winning support from some military veterans on Twitter.

The 49ers quarterback sparked controversy during the NFL’s preseason by sitting instead of standing during the “The Star-Spangled Banner.” Kaepernick says he’s protesting what he describes as oppression of minorities in the United States. Some who have criticized the protest said it was insulting to veterans.

But some people who identify themselves as veterans have tweeted pictures of themselves in uniform and messages of support under the hashtag #VeteransForKaepernick. One says he served to protect freedoms, not a song. Another says protesting is every American’s right.

Kaepernick says he will continue his protest before Thursday’s preseason game in San Diego and in the future.

His stance is prompting protests over a display at Reno-Tahoe International Airport that includes memorabilia from his days at the University of Nevada, where he starred before being drafted by the 49ers. A spokesman said the airport has received more than a hundred angry messages by phone, email and social media from locals and travelers who want Kaepernick’s trophy, helmet and other memorabilia removed from the prominent display case. Others passing by have offered disapproving hand gestures, hisses and venting.

“The toughest ones are the ones that come from veterans,” airport spokesman Brian Kulpin said. “There’s very strong feelings.”

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Kaepernick said last week that he’s refusing to stand for the national anthem because he believes the United States oppresses African-Americans and other minorities. The biracial Kaepernick has been outspoken on his Twitter account on civil rights issues and in support of the Black Lives Matter movement. He sat through the anthem during the 49ers’ three preseason games.

While at Nevada, Kaepernick became the only player in NCAA history with three seasons of 2,000 yards passing and 1,000 yards rushing. He was drafted by San Francisco in 2011.

Kulpin said the community airport never has seen such an outcry as the one prompted by Kaepernick’s items. The 20-foot-long glass display case highlights the University of Nevada in Reno, including its history and academics and sports programs. Featured in the primary concourse and visible to all passengers who go through security, Kulpin said the decorative display always has been popular, especially the Kaepernick items that were added about three years ago.

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“It’s the only thing in the public eye that is a shrine to Colin Kaepernick,” Kulpin said.

The display’s contents are owned and managed by the university and are due for an update in the coming months. There was a brief mix-up Monday when the Kaepernick items were removed temporarily for a cleaning and then placed back in the display.

Nevada associate athletic director Chad Hartley said changes had long been planned and are unrelated to the Kaepernick firestorm, though the school hasn’t been immune to the feedback. “We’ve seen some messages,’’ Hartley said. “We’ve heard from fans. But we’ve heard on both and all sides of the issue.”