NORRISTOWN, Pa. (CBS) – A 34-year-old Norristown man will spend at least 8½ years behind bars for stalking a teenager inside a local Walmart store last year and then trying to rape her after breaking into her home.

Judge Steven O’Neill says he considers Seth Griffith (above) a dangerous man and called the crime “chilling and horrific.”

On Friday, O’Neill sentenced Griffith to 8½-30 years in state prison for attempted rape, burglary, and related charges. A jury found Griffith guilty in May.

Montgomery County prosecutor Samantha Cauffman argued for a long sentence, calling Griffith “scary” because he still believes the woman made suggestive gestures inside the store.

“Because maybe she twitched her clothes or put her hair behind her ear — an innocent gesture anyone of us could do — and he took that as a sign, an invitation for him to have a sexual encounter with her,” Cauffman said.

Griffith followed the girl home to Audubon, burglarized the house, and then assaulted her in a bedroom in a terrifying 30-minute ordeal. He was arrested several days later in Nevada.

Reported by Brad Segall, KYW Newsradio 1060.