Marjory Stoneman Douglas High School student Cameron Kasky speaks at a rally for gun control at the Broward County Federal Courthouse in Fort Lauderdale, Fla., on Feb. 17. (Rhona Wise/AFP/Getty Images)

Organizers of a rally against mass shootings planned for next month in Washington are expecting up to 500,000 attendees, according to an event permit application.

The application filed this week with the National Park Service indicates the “March for Our Lives” will be March 24, although a location hasn’t been determined. The rally, organized by survivors of last week’s school massacre in Parkland, Fla., will have “sister marches” in other major cities, organizers said.

The event will include “student speakers, musical performers, guest speakers and video tributes,” according to the permit application, with 14 Jumbotrons and 2,000 chairs.

Mike Litterst, a spokesman for the National Park Service, said that organizers initially proposed holding the event on the Mall but are looking at moving the rally to another location in Washington after the request conflicted with a film crew’s permit.

A superintendent threatens to suspend students protesting gun laws. But that’s not legal.

Students of the Florida school where 17 people died last week announced nationwide marches for gun control on March 24. (Video: Patrick Martin/The Washington Post)

“We’ve had our first meeting with the organizers and for scheduling and logistics reasons they are now focusing on alternate locations for the event, including Pennsylvania Avenue and West Potomac Park,” Litterst wrote in an email. He added: “It’s the start of a fairly long and complicated process.”

Litterst said a march away from federal property would require a permit from D.C. police. A D.C. police spokesman said organizers have applied for an event permit with the city, but details about that application weren’t available Thursday.

The National Park Service permit application was filed by ­Deena Katz, identified by the Miami Herald as the co-executive producer of “Dancing With the Stars,” who was brought in by students to plan the event. Organizers have secured nearly $2 million in donations via a GoFundMe page, along with donations from Oprah Winfrey, Steven Spielberg and George and Amal Clooney.

“March For Our Lives is created by students across the country who will no longer risk their lives waiting for someone else to take action to stop the epidemic of mass school shootings that has become all too familiar,” the permit application read. “In the tragic wake of the seventeen lives brutally cut short in Florida, politicians are telling us that now is not the time to talk about guns. March For Our Lives believes the time is now.”

Katz couldn’t be reached for comment Thursday.

Shooting survivor Cameron Kasky, a junior, initially said the march would include a protest outside the White House in which unloaded AR-15 rifles, the weapon used by the Parkland gunman, would be destroyed. In an email Saturday, he said marchers no longer planned to smash AR-15s because of legal concerns.

Kasky said legislators and President Trump must do more to get such weapons out of the hands of civilians.

“I think the policymakers in Washington are starting to see a change within themselves,” he said. “I think that everybody deserves a fresh start. If they are not willing to have fresh start, then they will have a badge of shame.”

The rally’s website and Facebook page indicate marches in London, Philadelphia, Houston and Broward County, Fla., where a gunman killed 17 people at Marjory Stoneman Douglas High School on Feb. 14.

Florida students plead with Congress: It’s about the guns

In the video announcing the rally, shooting survivor Emma González said students wanted conversations with President Trump, Sen. Marco Rubio (R-Fla.) and Florida Gov. Rick Scott (R) about their support from the NRA and to “give them the opportunity to be on the right side of this.”

“If they don’t turn around right now and state their open support for this movement, they are going to be left behind,” González said. “You are either with us or against us.”

On Tuesday, Winfrey tweeted: “These inspiring young people remind me of the Freedom Riders of the 60s who also said we’ve had ENOUGH and our voices will be heard.”

If the march draws 500,000 attendees, it would be one of the largest in Washington in recent years and in line with last year’s Women’s March on Washington. About 1.8 million people attended President Obama’s inauguration in 2009.

Read more:

‘Heroic’: West Point admits a student who was killed in the Parkland shooting

No. 2 FBI official addresses criticism over fumbled tip on Nikolas Cruz