WASHINGTON (CNN) -- Some experts are skeptical that anything could have stopped Robert Hawkins from going on a murderous rampage at an Omaha, Nebraska, shopping mall on Wednesday. A police car sits outside the Westroads Mall in Omaha, Nebraska, on Thursday. "This is not something that anybody can reasonably anticipate," said Don Greene, a former FBI agent who has written a book on mall security. "If the people closest to him didn't see any indicators or signs that he was going to go off so drastically ... how is some public safety officer supposed to recognize this person?" Greene asked.
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Malls expected to assess security arrangements in wake of Wednesday shooting
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Gunman at Omaha, Nebraska, mall killed 8 people and himself
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Some security experts say such incidents are impossible to anticipate
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Study by Police Foundation says training drills for mall guards are inadequate
The @placeholder also sends out alerts regarding possible threats to the private sector -- but warnings of possible terrorist plans are clearly of no help in anticipating an attacker like Hawkins.