GRAND RAPIDS, Mich. – A retired Army officer who is an expert on violence told an audience at a recent forum that “Sandy Hook is only the beginning” and schools should prepare students for armed intruders.

Lt. Col. Dave Grossman was a speaker at this week’s Crime Stoppers USA annual training conference. He told an audience of about 100 people that school shootings remain a distinct possibility in our increasingly violent society, according to a report from MLive.com.

Grossman said the best strategy is to train students in self-preservation techniques in the event of an armed intrusion. He said they should learn diversionary tactics, like throwing a book to momentarily distract shooters, and should be taught to run instead of sitting still and waiting for potential disaster, he said.

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Easy targets are the first victims, so kids should learn how to be difficult targets, he said.

“Our schools have got to prepare for the possibility,” Grossman said. “You want them to sit there and wait for their turn to die? We are negligent if we don’t (prepare them).”

Grossman said America’s fascination with television shows, movies and video games with violent themes can be blamed for the increasing number of random shootings, according to the news report.

He said video games with violent themes, and their interactive nature, have been proven through research to create dangerous behavioral changes in users. Some of those users will carry their penchant for video violence into real-life situations, creating danger for everyone around them, he said.

“They change the mindsets of people who play them,” Grossman said.