Stunned by the deadliest high school shooting in U.S. history, students mobilized across the country on Sunday to organize rallies and a national walkout in support of stronger gun laws, challenging politicians they say have failed to protect them.
Students from Marjory Stoneman Douglas High School, where a former student is accused of murdering 17 people on Wednesday using an assault-style rifle, joined others on social media to plan the events, including a Washington march.