39 starved horses found locked up in feces-filled Washington farm (VIDEO)

Thirty-nine starved horses, many of them injured, were found in three Washington farm being operated like a "puppy mill," officials told Reuters, describing some animals found standing in more than a foot of trash and excrement. 

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US Drug Enforcement Administration officials found the animals on Wednesday while pursing drug-related charges at the Graham, Washington farm, near the city of Tacoma in Pierce county, local animal control supervisor Brian Boman told Reuters.

"It was like a puppy mill, only with horses," Boman told Reuters. "The conditions are terrible. There's no telling how long it's been since they've seen daylight."

Britain's Daily Mail has published pictures of the poor horses, which included pure-bred Arabians, Belgian Drafts and Clydesdales. 

It took more than nine hours to roundup the traumatized animals, officials told Reuters. They have been taken to a clinic and some of the more critical cases are expected to have to be put down. 

The Pierce County Sheriff's Office said it was such seizure in the country's history. "Most of the horses were in barns that had large amounts of urine and feces in the stalls," the release said, according to Reuters. "Some of the barns had no lighting or ventilation and the smell of ammonia was very strong."

The name of the farm has not been released because it is subject to a criminal case, according to Reuters. 

The Daily Mail also featured the following video taken from local reporting: