NRA supporters take up positions in the median of Pennsylvania Avenue in a counterprotest as gun-control activists participate in a rally at the Justice Department headquarters in Washington in 2017. (Pete Marovich for The Washington Post)

Halfway through their national tour of registering young people to vote and raising awareness about gun violence, survivors of the Marjory Stoneman Douglas High School shooting will step off their bus Saturday in Virginia at the Fairfax County headquarters of the National Rifle Association.

The teens will be joined by activists, protesters and survivors of gun violence to protest the NRA’s role in blocking gun-control legislation and defending sales of guns such as the AR-15, the semiautomatic rifle used in the Parkland, Fla., massacre.

The protest, dubbed the “National March on the NRA,” will begin at noon. It is expected to last three hours.

Demonstrators say they will come with a number of demands and policy proposals.

Among them are a ban on high-capacity magazines and “any weapon of a caliber higher than .30-caliber or more and any rifle, long gun, or short-barreled rifle that fires in semi-automatic and takes self-loading magazines,” and the institution of universal background checks through the National Instant Criminal Background Check System. They also want a searchable database of gun owners run through the Bureau of Alcohol, Tobacco, Firearms and Explosives.

Protesters say they will demand that the Internal Revenue Service revoke the nonprofit status of the NRA and that the House Appropriations Committee approve funding for the Centers for Disease Control and Prevention to research gun violence and its impact on public health and safety.

“They’re in this little corner of Virginia, and when we march in D.C., they don’t have to see us,” said Lawrence Nathaniel, 25, executive director of the National Organization for Change. “So we wanted to go out there to them and shut down the road and say: ‘Look, we’re here now. You have to listen.’ ”

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Though most NRA workers won’t be in the office Saturday, the NRA’s National Firearms Museum will remain open as police shut down Waples Mill Road in Fairfax to accommodate crowds.

“I originally wanted to plan the protest on a Friday or Thursday so we could catch people in the office, but it was hard,” Nathaniel said. “Our organizers have school or other work, and then the March for Our Lives organizers asked us to change the date so it would coincide with their bus tour coming through town, so it’s Saturday.”

He said the NRA warned organizers they would be met with counterprotesters demonstrating against stricter gun laws.

The NRA did not respond to a request for comment on the protest or possible counterprotesters.

Lt. Eli Cory of the Fairfax County police said officials did not expect the two groups to clash, adding that authorities will “allow everyone to safely exercise their First Amendment rights.”

Several survivors of the Feb. 14 shooting in Parkland are expected to attend the rally, which will include 11 speakers and performers addressing the crowd from a stage. Among them will be student activists, as well as Fred Guttenberg and Manuel Oliver, parents of students killed in the Parkland shooting. Oliver painted a bloodied portrait of his son, Joaquin, outside an NRA convention in Dallas.

Attendees will also be able to register to vote, play games, win prizes and view art displays created in response to recent shootings. Organizers expect as many as 4,000 people to attend.

Several students from Great Mills High School in Southern Maryland said on social media that they planned to attend. Great Mills students were thrust into the national spotlight earlier this year after a 17-year-old student brought a gun to school and fatally shot Jaelynn Willey, 16.

Days after a shooting, Great Mills students join D.C. anti-gun rally

Students from New York, Illinois, Georgia and elsewhere will arrive by bus, organizers said. Similar “sister marches” will take place in nearly two dozen other cities, where marchers will target local guns groups or state legislatures.

“I’m from a community where gun violence is rampant,” said Nathaniel, a native of Orangeburg, S.C. “A lot of us have been touched by gun violence in places like that where it’s so easy for people to get guns and it’s so easy for kids to get their hands on guns.”

Fairfax police said they were unaware of any credible threats to the protest, which has drawn virulent opposition in other states.

According to the Denver Post, students in Colorado were reconsidering their protest this week after receiving threats indicating someone would bring a 3-D-printed gun to the rally. In a Facebook comment directed at the gun-control group Never Again Colorado, a commenter wrote, “My rights are worth more than your life.”

Cory said Fairfax police will close several streets around the NRA building as a precaution. Waples Mill Road will be blocked from Pender Drive to Sarah Harper Way, about a third of a mile.

Drivers will be advised of detours via message boards and social media. Fairfax residents should expect to see an “increased public safety presence in the area,” according to police.

This is not the first time the NRA building has been the center of protests and vigils. Hundreds rallied outside the group’s headquarters days after the Parkland shooting left 17 students and school staffers dead. Police said small gatherings of protesters outside the NRA usually convene at least once a week, but they stick to the sidewalk.

The symbolism of rallying outside NRA headquarters was important to Nathaniel and other organizers, but, he said, he has no illusions about changing the group’s political positions.

“The NRA has the ability to be the organization that fights for Second Amendment rights while also fighting to protect each and every American citizen, but they choose not to,” he said. “They’d rather threaten and antagonize us than sit down and talk about how we can work together to make sure every American has a quality and safe life.”

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