According to Erie County Coroner Lyell Cook Rieger died of a gunshot wound to the chest. Riegers death is the eighth homicide in the city this year.
Diaz was taken into custody late Friday night at a west side tavern. He faces charges of criminal homicide, murder, aggravated assault, recklessly endangering another person, possession of a weapon, and firearms not to be carried without a license.
Diaz is in the county jail and is ineligible for bond.
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