The Madison County Sheriff's Office is mourning one of its own after a police K-9 died during training Wednesday.

A sheriff's office spokesman did not release any information about the dog, including how old it was or how long it had been with the sheriff's office. An autopsy is being performed to determine the cause of death, the spokesman said, and more information would be released once the autopsy was complete.

WAAY 31 spoke with a veterinarian who said it could have been any number of issues.

"Heat could have definitely played a part in it," Animal Care Clinic veterinarian Dr. Kevin Anderson said. "There could be heart problems that are undiagnosed. That's always a problem that you could have if it was undiagnosed. It could have thrown a blood clot--had an accident there. Make sure your dogs are on heartworm prevention because heartworms can cause sudden death like that in a dog. But without an autopsy or necropsy there's just no way to tell."

There's no word when the autopsy might be completed.

The sheriff's office has three other K-9 officers.