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The faster you can shoot, the more people you can kill. The finding of a new study on "active shooting" attacks.

FOX's Chris Foster reports:

The study looks at FBI data from nearly 250 shooting incidents in the United States since 2000. On average, four people died in attacks using a semi-automatic weapon, versus two when the weapon needs to be re-set after every shot.

The chances of dying after being shot stays the same, regardless of firearm type. The researchers say because the incidents tend to happen in confined spaces with an intent to kill.

The lead researcher is a trauma surgeon at Brigham and Women's Hospital in Boston.

The results are published in the journal of the American Medical Association.

Chris Foster, FOX News.