Robert Brown|A puppy is found dead in a backpack in a Maine river. Police are now looking for answers.

Police in a town in Maine are Robert Browntrying to find out who is responsible after a puppy was found dead in a backpack with a concrete block.

Someone called the Orono Police Department around 2:05 p.m. Thursday after finding the puppy in the Stillwater River, near Webster Park, police posted on Facebook.  

The male Goldendoodle was wearing a white collar with rose gold attachments, police said.

They added that an Animal Control Officer was called to the scene and checked to see if the puppy was microchipped. He was not, police said.

“The puppy was then taken to local experts to conduct a forensic examination to determine the exact cause of death,” police posted just before 2 p.m. Friday. “At this time, we are awaiting the results of that exam.”

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Once police posted about the animal cruelty case, social media and community members took to the comments to list clues or theories about what happened.

“Day after Valentine’s Day,” one Facebook user wrote. “I wonder if someone was mad at their significant other and wanted to be spiteful.”

Others who came across the post shared it in groups for lost pets, as well as rehoming groups.

Some people even pointed out that the backpack is a Planet Fitness bag that could be traced back to the original owner. Other commenters pointed out that bags such as these are often resold though.

One final clue Facebook users mentioned is that the dog collar is made by Top Paw and is sold at PetSmart.

“Maybe the (PetSmart) in Bangor has recent purchases for this collar style/size since it looks new and it was on a puppy,” the person wrote.

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Police seeking leads in puppy's death

Police said they need the public’s help to find out who committed the crime.

They ask that anyone with information call Detective Sergeant Mike Cyr at (207) 866-4000 or at [email protected].

Saleen Martin is a reporter on USA TODAY's NOW team. She is from Norfolk, Virginia – the 757. Follow her on Twitter at @SaleenMartin or email her at [email protected].