Factbox: Major shootings at schools in the United States

A "wall of Demand" mural and video message created by Manuel Oliver is seen one year anniversary of the school shooting in Parkland Florida in New York

(Reuters) - Below are some of the bloodiest and most notable U.S. mass shootings at schools in recent decades, ranked by death toll. This is not a complete list of all major U.S. mass shootings:

VIRGINIA TECH, April 16, 2007 - A gunman slaughters 32 people and kills himself at Virginia Tech, a university in Blacksburg, Virginia.

SANDY HOOK, Dec. 14, 2012 - A man fatally shoots his mother, then kills 20 children and six adults before killing himself at Sandy Hook Elementary School in Newtown, Connecticut.

PARKLAND, Feb. 14, 2018 - A former student at Marjory Stoneman Douglas High School in Parkland, Florida, opens fire with an assault-style rifle, killing 17 students and educators. Authorities arrest the gunman.

AUSTIN, Aug. 1, 1966 - A sniper perched in a University of Texas clock tower unleashes 90 minutes of terror by killing 13 people plus a fetus and wounding more than 30 others in what is regarded as the first U.S. mass shooting in a public space. He is fatally shot by police.

COLUMBINE, April 20, 1999 - Two teenagers rampage through Columbine High School in Jefferson County, Colorado, fatally shooting 12 students and a teacher and wounding more than 20 others before killing themselves.

(Reporting by Brendan O'Brien in Chicago; editing by Jonathan Oatis)