CRAWFORD COUNTY, MI -- As deputies investigate the sexual assault of a puppy in Northern Michigan, the Humane Society of the United States is offering a reward in hopes of identifying the person responsible.

Jake, a 14-week-old Malteze Shih Tzu puppy, went missing from his owners' backyard in Grayling on March 12. Several hours later, he returned covered in mud and shaking.

The puppy wouldn't lift his tail during a bath, and it was determined by veterinarians that he was the victim of a sexual assault.

The Humane Society is offering up to $5,000 as a reward for information leading to the identification, arrest and conviction of the person responsible.

"Anyone who would deliberately abuse this sweet little dog like that is a danger to the community at large," said Jilly Fritz, Michigan senior state director for HSUS, in a statement.

The Crawford County Sheriff's Office is investigating the case. Anyone with information is asked to contact central dispatch at 989-348-6341.