The case of dogs found skinned and mutilated along a county road in Berthoud, Colorado has residents upset.

Investigators in Larimar County are searching for the person responsible for skinning and mutilating the two dogs, found outside of Berthoud last week, according to CBS Denver.

The dogs were found a few miles apart on the highway, but were so badly abused that veterinarians can't even tell what breed they were, the news station reports.

Police received an anonymous call tipping them off about the first dog. Responding to the call, law enforcement officers found the first dog alongside County Road 4.

Police told CBS Denver the dog was skinned and beheaded. Its tail was also removed.

The dog was a female, authorities said.

On Saturday, a similar case was found on County Road 16, just a few miles away from the first finding. The dog was skinned and brutalized in a similar manner, authorities said.

Investigators have no leads, but the dog carcasses have been sent to Colorado State University for tests.

Local Humane Society spokesperson Marcie Williams told the Daily Mail injuries appear to have been caused by a human, adding, it is a heartbreaking situation.

We just get so many animals that come into Larimer Humane Society that are stray every year and at this point we don't even know the specific breed of the animals, Williams said.

See a video about the investigation below: