Authorities have seized dozens of horses from a property near Graham after federal authorities discovered what appears to be a breeding operation.
"Think puppy mill, but for horses," said Det. Ed Troyer with the Pierce County Sheriff's Office.
Among the 39 horses recovered at the property near the 30800 block of Meridian East were a dozen Arabians.
"The conditions are deplorable," Troyer said. "I don't think any living thing should live like these horses are. They're standing in a foot deep of manure. It doesn't look like any of their stalls have been cleaned. They're caged up. It's just not right."
According to Pierce County Animal Control, many of the horses had medical issues and some were very thin.
"This is the largest seizure of horses that Pierce County Animal Control has ever undertaken," said Julie Anderson, Pierce County Auditor. "Many of the horses appeared to have been kept in conditions with no sunlight or ventilation and (they) are very scared."
Troyer said the operation would continue throughout the day Wednesday and that multiple agencies and veterinarians are involved.
The animal owners could face charges of second-degree animal cruelty.
The Associated Press contributed to this report.