Maricopa County, Arizona, law enforcement authorities are seeking whoever shot and killed a foal belonging to the Salt River horse herd, which is protected under state law.

The Salt River herd is made up of feral horses is not protected by federal law. However, earlier this year, Arizona legislation making it unlawful to harass, shoot, injure, or slaughter a Salt River horse and placing the animals under Maricopa County Sheriff’s Department and U.S. Forest Service jurisdiction was signed into law.

Maricopa County Sheriff Joe Arpaio said witnesses reported seeing someone shooting at three Salt River horses with a rifle on Oct. 21. A foal aged 7 to 10 months old was fatally shot in the head and neck, Arpaio said. It is unknown whether the other two horses were wounded or killed, he said.

“We sent up our helicopter this weekend when we got the call, but we found nothing,” Arpaio said. “Now, we’re sending out a mounted posse to find the other two horses