Police Sgt. Drew Sanders released a statement Friday saying answers are slow in coming after Sierra Newbold was found dead in a canal near her home June 26. Family members reported her missing from her bedroom shortly before the body was discovered.
An autopsy revealed Newbold had also been sexually assaulted.
Police say the family has been cooperative in the investigation. Newbold's father released a statement earlier this week calling his daughter "a bright star" and saying family members are devastated by the loss.
Police say finding who is responsible is the department's top priority.
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