Hartford Police haven't given the exact details about what the argument was about, but say there was no history between the neighbors.
Two people, 39-year-old Chase Eugene Garrett and 27-year-old Christina Dang, were shot and killed.
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3 members of the same family killed in Queens fire
A third person, who hasn't been identified, is still in the hospital with what police call "critical injuries."
There have been 20 homicides in Hartford so far this year.
There were 19 total last year.
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