U.S. authorities are investigating after at least 15 horses were reportedly found fatally shot Tuesday near a strip mining site in Eastern Kentucky.

The horses were found near U.S. Highway 23, WYMT reported.

Some of the horses were only 1 year old or younger, and some were pregnant, according to authorities, who added that it appears the horses were shot with a low-caliber rifle.

“This is very inhumane, and it’s a very cruel act of somebody who just apparently had nothing else to do or whatever, just to go back on a strip job and shoot down horses who were, one of them obviously was feeding, had grass in its mouth,” Floyd County Sheriff John Hunt told WYMT. “It looked like a battlefield for just horses.”

Hunt added that it was one of the worst cases of animal cruelty he has ever seen.

At a minimum, the perpetrator of the violent act will likely face animal cruelty charges, according to authorities.

Hunt said authorities spent most of Tuesday morning trying to reach the strip mine location to confirm the number of horses that had been killed, but rainy weather made travel difficult up the hillside, according to the Floyd County Chronicle & Times.

Hunt also said most of the horses “were scattered out.”

A veterinarian will reportedly conduct a field necropsy on one of the horses to confirm the cause of the deaths.

The US$500 reward for information on the incident is now reportedly estimated to be more than US$5,000.  (SD-Agencies)