President Donald Trump and Vice President Mike Pence are headed today to Dallas, Texas, where they’re set to address an annual convention of the National Rifle Association. The Secret Service has banned firearms, knives and other weapons from today’s event, which comes on the heels of high-profile mass shootings, including last October’s massacre in Las Vegas—the worst in modern U.S. history—and the Marjory Stoneman Douglas High School massacre in Florida, which sparked a national movement of students protesting for gun control laws. Last year Trump became the first U.S. president since Ronald Reagan to address the NRA.