Police say a new DNA match could lead to the capture of a killer and rapist with cold case victims in South Carolina, Tennessee and Missouri

A recent DNA match has linked three long-unsolved crimes — a double-homicide, a homicide and a sexual assault — across three states dating back to 1990, PEOPLE confirms.

Now, authorities tell PEOPLE they are confident they will capture the suspect, who they described as a “serial killer.”

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Authorities say they believe the April 1990 killing of Genevieve Zitricki in South Carolina was the first in the crime spree that lasted at least eight years, according to Captain Chris Hensley with the New Madrid County, Missouri, Sheriff’s Office.

“I’m confident that we’ll identify the killer,” Hensley tells PEOPLE. “It’s the when will we identify him that I’m not sure about.”

Zitricki, 28, had been beaten, sexually assaulted and strangled after the suspect broke into her Greenville home, according to USA Today. Her body was found in the bathtub days later.

Image zoom Genevieve Zitricki New Madrid County Sheriff's Department

A double-homicide and shooting eight years later provided a potential break in the unsolved case when Sherri Scherer and her 12-year-old daughter Megan were found dead of gunshot wounds in their Portageville, Missouri, home. The suspect “used a ruse” to gain entry to the family’s house, Hensley says.

“Once inside the house, that’s when he gained control of them and used restraints,” he says, noting that Megan was sexually assaulted. “We believe that he was asking for directions or for some help, maybe he was saying he had some car trouble. We’re not sure.”

Image zoom Sherri (bottom left) and Megan (bottom right) Scherer with family New Madrid County Sheriff's Department

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DNA evidence taken from the scene matched that found in Zitricki’s killing, Hensley says.

Officials said they believe that after the double-homicide, the killer “went just across the state line” and shot a woman in Dysersburg, Tennessee.

“She knew something was wrong and he actually pulled a weapon on her outside of the home,” Hensley tells PEOPLE of the mother, noting that the killer tried to get into the family’s house. “That’s when the struggle began and she was able to get back inside the house with her children and hold the door shut and he fired through the door and hit her around the bicep.”

Earlier this month, police learned that DNA evidence from a 1997 sexual assault in Memphis was linked to the double-homicide in Missouri and, ultimately, Zitricki’s killing.

The suspect knocked at the front door of the Memphis home and used a revolver to threaten three woman and a minor, Hensley says. He bound the victims before sexually assaulting the young girl.

Hensley says he is confident that the same suspect, described as a white man with a mustache and glasses, committed all of the crimes.

“We’re very dedicated,” he tells PEOPLE, adding that he and a Missouri Highway Patrol sergeant investigate the cases constantly.

“We look over leads. We make phone calls to other agencies. It’s something that is worked on every day.”