BALTIMORE (WJZ) — About five weeks ago, police say 19-year-old Nikolas Cruz walked into Marjory Stoneman Douglas High School, armed with an AR-15 assault-style rifle, and fatally shot 17 people.

Since then, students from the Parkland, Florida school have been very much in the public eye, forming the “Never Again MSD” group and fighting for gun control and increased school safety.

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They organized a nationwide school walkout last week, on the one-month anniversary of the shooting at their school, and they have been instrumental in planning this Saturday’s March for Our Lives rally in D.C.

A petition associated with Saturday’s march calls for banning sales of assault weapons and large-capacity ammunition magazines, as well as tightening background checks.

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More than 800 March for Our Lives demonstrations are planned around the world.

On Tuesday morning, shortly after shots rang out in the hallway of a Maryland school, Great Mills High in St. Mary’s County, some of the Parkland students were tweeting about it, sending supportive messages and condolences.

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