Oregon State Police has suspended its investigation into the deaths of two wolves in Wallowa County.
The agency said Wednesday there was too much decay to determine what caused the deaths.
Last month, the agency said it suspected a person or people had killed the wolves.
The bodies were found 50 yards apart in August. One of the wolves was collared and its collar emitted a mortality signal, leading to the discovery.
The Oregon Department of Fish and Wildlife said the pair had become officially established in the Sled Springs area in January.
ODFW said there was one reported wolf predation in the area in June, when a rancher found a partially consumed calf and the state determined it was killed by a wolf.
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