IL: Armed Samaritan uses AR-15 to Stop Knife Attack

The witness, who spoke with WGN-TV, said he ran to grab his AR-15 after hearing the commotion and spotting a "pool of blood" in his apartment building hallway. "Blood was everywhere," said neighbor Dave Thomas, adding that he chose the AR-15 over a handgun, saying, "Bigger gun, I think a little more of an intimidation factor. Definitely played a part in him actually stopping."

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