RCMP say they have made an arrest in the case, but added they wouldn't release any names in order to protect the child's identity.
Police say the girl was transported to hospital by helicopter and that while her condition remained critical on Sunday, she was stable.
Global News in Edmonton reported that family members said the child had been skating with friends on Saturday and was then left at home with a family member.
Neither were there when others returned to the house, and it was initially assumed she had returned to the rink.
Global reported the family members it interviewed say she was later found beaten and naked in the woods.
RCMP say they are continuing to investigate the case, along with police from Edmonton's major crimes unit.
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