"The emotional rollercoaster has been pretty terrible," she said. "I want to see whoever did this get caught and justice for my dad and for this second lady and hopefully no more [killings]."
The family of Carswell declined to comment and said that police had asked them not to make any statements. Carswell lived in nearby Hernando, Miss., and worked at a casino.
The shootings appear to be random and there is no known connection between the victims. Police are analyzing shell casings discovered at both scenes.
Authorities have launched a dragnet, saturating the area, looking for clues and a possible suspect.
"We do not have any witnesses at this point," DeSoto County District Attorney John Champion told the Associated Press. "We're asking the community for help."