Two dogs described as "pit bull mixes" attacked a Florida girl’s miniature horse Monday after digging under a guard fence and attacking the defenseless animal, reported.

"That was the worst I’ve seen in my life," James Baxland, a family friend who raised horses for 20 years and saw the horse's injuries. The horse was eventually put down.

Deborah Johnson, who lives in Rearview, a town outside Tampa Bay, bought the horse as a Christmas present last year for her granddaughter. The girl grew a bond with the horse.

"I don't know what to tell my baby," she said.

Animal services took one of the dogs into custody. The dog’s owner told the station that the dog did not attack the horse.

"This is my dog and I know that he did not do it," the owner said.

Pesco, the dog, is being held under quarantine at animal services for 10 days. If investigators do not find any other attacks in his history, he will more than likely be released.

Animal services is still investigating and looking for the second dog involved.

Click for more from