Looking back, some are saying there were signs 19-year-old Nikolas Cruz was on the brink of a homicidal attack.

Cruz is the gunman who police say killed 17 people and wounded 14 others at a high school in Parkman, Florida on Wednesday Feb 14.

West Michigan security expert Jason Russell of Firestorm Solutions says there are always warning signs that precede an active shooter attack.

Investigators say Cruz posted disturbing material on social media after he was expelled from Marjory Stoneman Douglas High School. There are also reports he was obsessively stalking a girl in the school. He had a semi-automatic rifle and a stockpile of loaded magazines.

“And some of the things we are hearing in this situation are the things I hear over and over again from previous attacks,” says Russell. “We just have to do a better job picking up on those things and hopefully intervene. It is never going to be perfect but we have to make an effort.”

Russell recommends a layered prevention plan that includes locks, cameras and physical security along with more attention to behavior and actions that might signal danger is imminent.

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