(CNN) -- A 19-year-old Kentucky woman who has been missing for more than a week is believed to be with a registered sex offender who has a history of kidnapping and unlawful confinement, authorities said Tuesday. Brittney Kustes was last seen July 17 at her grandparents' home in Brooks, just south of Louisville, according to Detective Scott McGaha of the Bullitt County Sheriff's Office. Witnesses told police that sex offender Roy Vernon Elwell, 34, was seen driving up and down the street where Kustes' grandparents live on the day she disappeared. "Shortly after, she was gone," McGaha told CNN. Since her disappearance, multiple people, including friends of Elwell's, have reported seeing the pair in Louisville and the surrounding areas.
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Brittney Kustes, 19, was last seen July 17
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Witnesses have reported seeing her with 34-year-old sex offender Roy Elwell
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Her mother says Elwell introduced Kustes to methamphetamine
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"She hated this guy, actually," her mother says
She said the last time @placeholder was with her daughter, Brittney returned home addicted to methamphetamine, a drug habit she had recently kicked.