1 / 18

Virginia Tech

Members of the Virginia Tech Corps of Cadets stand guard for 32 minutes following the lighting of a ceremonial candle at midnight on the Virginia Tech campus, Monday, April 16 2012, in Blacksburg, Va. The candle will remain lit for the duration of the day and will be guarded again by cadets for 32 minutes prior to removal at midnight. Each anniversary since the April 2007, massacre on the Virginia Tech campus, classes have been suspended for the day in memory of the 32 students and faculty killed in the rampage by a lone gunman who then killed himself. On Monday, the fifth anniversary of the deadliest mass shooting in modern U.S. history, the 28,000 students on campus will head to class to honor the 32. (AP Photo/The Roanoke Times, Daniel Lin)

Virginia Tech marks shooting anniversary

Virginia Tech on Apr 16 marks the fifth anniversary of the deadliest act of gun violence in modern U.S. history, a massacre that killed 32 people, prompted congressional action and spurred universities nationwide to enhance their alert systems.