Story highlights Detective: "I don't know why someone would shoot two defenseless men"

Shootings happened within 3 miles of each other

The bullets used are fairly distinctive

Atlanta (CNN) Atlanta police are calling the shootings "sinister" because whoever pulled the trigger wasn't expecting to gain from them monetarily.

These were two homeless men, shot to death as they slept. And police aren't convinced the threat is over.

"A lot of our shootings involve robbery. A lot of our shootings involve someone making good on an old debt or some kind of revenge factor," Atlanta police Detective David Quinn told reporters Wednesday.

"I don't know why someone would shoot two defenseless men."

The shootings happened over the Thanksgiving week within three days of each other. The killer, or killers, haven't struck since, but police are asking the city's homeless to remain vigilant.

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