About 40,000 protesters showed up in D.C., according to organizers, along with thousands more in New York, Chicago, Las Vegas and Los Angeles. RELATED: House passes gun reform legislation following mass shootings Thousands of people rallied in the nation's capital and around the country Saturday to advocate for stricter gun control laws after a recent spate of mass shootings, including in Uvalde, Texas, where 19 children and two teachers were killed in a school, and in Buffalo, New York, where 10 Black people were targeted in a grocery store. The March for Our Lives events come four years after the organization was founded by teens who survived the 2018 Marjory Stoneman Douglas High School shooting that killed 17 people in Parkland, Florida. That year, more than 1 million people rallied in Washington. » Subscribe to USA TODAY: http://bit.ly/1xa3XAh » Watch more on this and other topics from USA TODAY: https://bit.ly/3MF3LWR » USA TODAY delivers current local and national news, sports, entertainment, finance, technology, and more through award-winning journalism, photos, videos and VR.