Washington — A corporation that breeds and sells animals to the scientific community for testing admitted to knowingly violating federal law when it failed to provide adequate care to thousands of beagles at its Cumberland, Virginia, breeding facility, the Justice Department announced Monday. 

Federal prosecutors sued Envigo RMS LLC in 2022, alleging the company neglected the dogs through inadequate veterinary care, insect-infested food and rampant unsanitary conditions. The lawsuit forced the company to forfeit more than 4,000 beagles that year to nonprofit organizations that put the rescued dogs up for adoption. 

At that time, Envigo also closed the Cumberland facility. 

In an agreement unsealed Monday, Envigo pleaded guilty to conspiring to violate the Animal Welfare Act, and its sister company, Envigo Global Services Inc., admitted to breaking the Clean Water Act when it let wastewater seep into a local waterway and adversely affect the dogs' health. As part of the agreement with prosecutors, their parent company, Inotiv, will pay $22 million in fines, plus millions more to improve their facilities and assist with environmental restoration. 

According to the Justice Department, the fines are the largest ever in an animal welfare case. 

"Envigo promoted a business culture that prioritized profit and convenience over following the law," U.S. Attorney for the Western District of Virginia Christopher Kavanaugh said in a statement. "This callous approach led to dire consequences: the inhumane treatment of animals and the contamination of our waterway." 

Inotiv said in a statement that it "fell short of our standards for animal and environmental welfare" and apologized to the public. "In resolving this matter, we renew our commitment to maintaining the highest standards of animal care, as well as to the communities and environments in which we operate. We hope that others will learn from our experience." 

Investigators alleged in the 2022 lawsuit that despite repeated warnings, the company failed to provide humane care to the thousands of beagles housed at the Virginia facility. Hundreds of the dogs there were found to have been in "acute distress." 

"Envigo's disregard for the law and the welfare of the beagles in its care has resulted in the animals' needless suffering and, in some cases, death," prosecutors wrote at the time, accusing the company of creating conditions in which the dogs could dangerously attack one another. 

The Humane Society, which led the operation to remove and find homes for the beagles, said in a statement that it is "grateful that those responsible for their suffering are being held accountable."

Robert Legare is a CBS News multiplatform reporter and producer covering the Justice Department, federal courts and investigations. He was previously an associate producer for the "CBS Evening News with Norah O'Donnell."