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Va. Tech has had series of scares since 2007

The massacre at Virginia Tech on April 16, 2007 still remains deadliest mass shooting in modern U.S. history, leaving 33 dead and wounding many more.

As two people were killed in a campus shooting Thursday, many are recalling the tragedy of 2007. While it took hours before school officials notified students about the previous incident, it took mere minutes to lock down the school today.

Since that date, the university has taken many strides into enforcing new emergency protocols on campus, including an alert system on their website, special message boards and sirens throughout campus, as well as a university-wide notification system through text and email to warn students of potential danger. Still, the university maintained today that they acted properly following the protocols that were in place in 2007.

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Since 2007, there have been several scares on campus. Shortly after the shooing, a carbon monoxide leak in an off-campus residence made 23 students sick, just one day before classes were about to resume.

The first time the revamped campus alert system was put to use after the massacre was in 2008, when an exploded cartridge from a nail gun produced sounds similar to gunfire near a campus dormitory.

It was next used in 2009 when a woman was decapitated while having coffee with a fellow student in a campus cafe. The school reported it sent 30,000 notifications by voicemail, email and text message, but they were not declared emergency alerts because the suspect was already in custody.

Recently, on August 4, 2011, students at a summer camp reported seeing a suspicious man holding what looked like a gun. Emergency protocol was put in place, but no one matching that description was ever found.