Law enforcement authorities in Colorado are hoping a cash reward will help them identify who is responsible for the shooting deaths of 13 horses last December.

Huerfano County Deputy Sheriff Ben Bounds said that on Dec. 21, 2011, the horses’ owner reported more than a dozen Paint horses–including a mare and her foal–missing when he failed to find them in their leased pasture near Gardner, Colo. The animals’ carcasses were later discovered scattered in various locations around the pasture, Bounds said.

"It is as though someone was stalking them," Bounds said.

He declined further comment on the continuing investigation