MAGNA — Police are investigating the deaths of nine horses that possibly died from dehydration.

A resident called animal control officers after finding the horses' bodies Friday in a field near the Pleasant Green Cemetery, 9200 W. 3500 South.

Police were told there could be as many as 20 horses in the several-acre field. Of the 10 horses they had located by Friday evening, only one was alive.

Representatives from Salt Lake County Animal Services and Mayor Ben McAdams' office were on scene Friday night as Sheriff Jim Winder led a mounted posse in search of any remaining animals.

Police were unsure how long the horses had been in the field.

Winder confirmed that the owners had an arrangement with another individual to be responsible for caring for the horses.

A water container was located in the pasture but was empty, said Unified police detective Ken Hansen.

"There doesn't appear to be any water here for them, so our first inclination is that it's a lack of water problem," Hansen said. "The horse that is alive has been taken (by its owner) to try to get it hydrated."

The 10th horse was reportedly improving Friday night.

Salt Lake County Animal Services is launching a criminal investigation into the horses' deaths. Director Mike Reburg said potential misdemeanor or felony charges could be filed depending on what investigators learn.

"It's really preliminary in terms of what the cause is and who may be at fault. That's what we need to work on in the coming days," Reburg said. "It's horrific what happened here."

The horses' owner reported he had driven past the field Tuesday and seeing them standing in the pasture didn't stop, Reburg said.

Magna resident James Burdett reported the horses to Unified police.

"Two days ago we smelled an odor of something foul and dead," said Burdett, who lives in a neighborhood near the field.

He couldn't see anything from his home at the time but eventually went looking and found the animals.

Burdett said he has also spoken to a representative from the Humane Society of Utah, who reported she knows the owners and contacted them.

"I haven't seen him, and like I said, there isn't water in any water troughs at all," said Burdett, who estimates up to 20 horses have been in the pasture before. "There could be more horses out there."

Burdett witnessed two horses die Friday. The saddest part of the day, he said, was that "this didn't need to happen."

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