LOUISVILLE, Ky. (WDRB) -- A Shelbyville man has been arrested after authorities say his 5-week-old girl was brought to Norton Children's Hospital with several fractured ribs.

According to an arrest report, authorities believe the girl suffered 14 rib fractures and a possible fracture of the femur.

"Some of the rib fractures were healing and some were new, indicating multiple occurrences," the arrest report states.

"I was just blindsided about it all," the girl's mother said. "She had a couple of bruises, but I just thought it was from maybe holding a little bit too tight or from the seat belt."

The Shelby County Sheriff's Office says 28-year-old Justin Lee Gylden was interviewed and admitted that between July 13 and Aug. 1, he had committed "abusive acts" toward the child while "under stress and frustration" -- and that the child was injured as a result.

The girl's mother, who didn't want to be identified, said Gylden was under some stress.

"He was stressed about finances, and I guess he just also tired too," she said. "He's not used to being around a newborn at all."

Det. Eric Hettinger said they police the abuse occurred over about a two-week period.

"Based on the fact that some of the injuries were healing ... we believe it was, was more than one instance," he said.

Gylden was arrested Tuesday night and charged with first-degree assault. He is currently being held in the Shelby County Detention Center..

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