Federal inspectors last week temporarily shut down a New Jersey veal processing facility after hidden camera footage emerged which appeared to show unethical treatment of animals.

The U.S. Department of Agriculture wrote in a letter to the Catelli Brothers slaughterhouse in Shrewsbury, New Jersey that it had reviewed five "covertly captured" videos that showed "egregious inhumane handling and slaughter of cattle" at the facility. In the videos, a calf is shown bleeding from open wounds and others appear unable to walk but are rolled and dragged by workers.

The USDA's letter did not specify the origin of the video, but the Humane Society of the United States claimed to be the organization that filmed it after infiltrating the slaughterhouse for more than a month in late 2013.

"This plant was slaughtering many calves, some called downer calves, too sick or injured to walk to their slaughter," said Paul Shapiro, a spokesman for the Humane Society of the United States.

On their website, the Catelli Brothers said they are one of the largest lamb and veal companies in the U.S., employing more than 250 people and supplying products to food chains like Acme.

"We are deeply concerned about the allegations that have been made regarding the care of calves at our facility," Tony Catelli, the President of Catelli Brothers, Inc., stated in an e-mail to ABC News. "Any mistreatment of animals at our facility is unacceptable, and our established practices strictly prohibit the processing of any downed calves."

He also promised full cooperation with the U.S. Department of Agriculture and stated the company had hired "one of the nation's leading experts on animal care and handling in meat plants" to help gather facts and identify necessary changes.

Acme confirmed they received meat from the Catelli Brothers but declined to comment further.

Shapiro said the temporary closure of the Catelli Brothers plant was "the right thing," but said the case also highlights what he called a loophole in federal regulations regarding "downer" cattle, or cattle that are disabled to the point that they cannot stand and walk on their own.

While downer adult cows cannot be slaughtered and sold for human consumption, federal regulations allow veal calves to " set aside to be warmed or rested" if they appear to be "non-ambulatory disabled" for potential slaughter later.

"I commend them [the USDA] for taking this action, but the USDA now has to finish the job and close the loophole on downer calves to stop the torment of these animals," Shapiro said.