Police say 31-year-old Daniel Lehi Ferry was arrested after investigators gathered information from a witness.
According to police, the witness reported seeing Ferry assault Anne Grae Kasprzak inside a home after she refused to have sex with him. The witness reported seeing Ferry then move her unconscious body into a car.
Police served a warrant at the home, where they say they found blood matching Kasprzak's.
The girl was reported missing on March 10 and her body was found on March 11 after a person walking along the Jordan River Parkway reported seeing blood near a pedestrian bridge.
Ferry was booked into the Salt Lake County Jail on suspicion of murder.
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