CHICAGO (CBS) — A University of Chicago terrorism analyst says the Boston Bomb placement shows it was designed not for maximum lethality but to send a message by maiming and wounding, reports WBBM’s John Cody.

“A natural tactic would have been to explode the bomb in the beginning part of the race when the runners and the crowd are truly packed together at the beginning, that is when much more likely many more people could have been killed,” said Pape.

Professor Pape, a political scientist, says investigative requests for all amateur video tapes will likely turn up pictures of the bombs being placed near the Marathon Finish line. He says there’s a better than even chance this will provide investigators with leads needed to find the bomber.

Professor Pape says he tends to rule out Al-Qaida as the bomber because if it were Al-Qaida, it would have claimed responsibility by now.

He says the relative crudeness of the bomb construction suggests a smaller group, though he won’t speculate whether domestic or foreign.

Pape’s now estimating there’s a better than 75 percent chance to bomber will be identified.

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