| − | Christopher Sean Harper-Mercer was a mass murderer, conducting a mass shooting at Umpqua Community College (UCC) in Oregon on October 1, 2015. See also: [[Young mass murderers]] | + | Christopher Sean Harper-Mercer was a [[Young mass murderers|young, mass murderer]], conducting a mass shooting at Umpqua Community College (UCC) in Oregon on October 1, 2015. |