RIVERSIDE, Calif. -- Riverside County sheriff's investigators are trying to decide if a crime was committed when a veteran Los Angeles County fire official crushed a puppy's skull with repeated blows from rock, but they have been unable to talk to the man.

"For several days, investigators have attempted to contact (Glynn Johnson) to ask if he is willing to provide more information about the incident," Investigator Cherie Blossfield stated Monday. "Attempts to contact (Johnson) by phone, at his home and through his employment have been unsuccessful so far."

Johnson, 54, is an assistant chief with the Los Angeles County Fire Department. He is in charge of several stations in eastern Los Angeles County.

The shepherd mix, Karley, was euthanized after the beating in Johnson's yard in the 17000 block of Armintrout Drive. A veterinarian told the owners, Jeff and Shelley Toole, that the dog had a crushed skull and brain damage, among other injuries.

Karley apparently got out of his yard and, about 4:30 that afternoon, neighbor Travis Staggs was walking it dog back to the Tooles.

But Johnson -- another neighbor who lives between the two -- stepped in and said he would take the dog back. Staggs told KTLA-TV that Johnson started beating the dog without provocation.

Johnson said the dog bit him.

According to Staggs, Johnson tried to break the dog's jaws by prying them apart, then started hitting Karley in the head with a big rock.

Police said they got a call reporting a dog attack about the same time someone else reported the attack on the dog. Apparently, the Tooles and Johnson had been at odds before Monday.

The Tooles said they planned to sue Johnson even if no criminal charges are filed.

Johnson went to a hospital for treatment of an injured thumb and wrist.