The 50 deaths, so far, are 18 more than the 32 people a gunman killed in the second most-fatal massacre, at Virginia Tech in 2007, according to data from Mother Jones that goes back to 1982.
The third-deadliest shooting was at Sandy Hook Elementary School in Newtown, Connecticut in 2012 when 22 first-graders and six adult school staff members were killed. The fourth highest death toll was in San Bernardino in December when 14 were killed.
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Next on the list of deadliest shootings is the 1999 tragedy at Columbine High School in Littleton, Colorado, when 13 people were killed by two fellow students. Near Littleton, at a movie theater in Aurora, Colorado, another shooting massacre occurred in 2012, killing 12.
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