A recent investigative report uncovered a disturbing series of experiments conducted by the United States government in which thousands of cats were killed and fed to other cats. Scientists working for the U.S. government killed an estimated 4,000 cats during the experiments, according to the report released by the watchdog group White Coat Waste Project (WCW).

The experiments involved feeding tissue from cat hearts, brains and tongues to other cats. Similar experiments conducted at the same U.S. Department of Agriculture lab in Maryland included feeding dog remains to cats as well as injecting cat remains into mice.

“Some of these cats and dogs were purchased by the government from the same Asian meat markets that the U.S. Congress roundly condemned in a House Resolution” the report stated.

The experiments—which included hundreds of dogs and took place between 2003 and 2015—were reportedly aimed at finding treatments for the very common parasite that causes toxoplasmosis.

WCW plans to release its findings in a report to Congress titled “USDA Kitten Cannibalism.”

The USDA never formally published their findings and attempted to bury evidence of the experiments, but they were recently uncovered through a FOIA request.

Sadly, the USDA’s Agricultural Research Service’s Animal Parasitic Disease Laboratory in Beltsville, Maryland is so notorious for cat killing experiments that Congressman Brian Mast of Florida recently introduced a bill to stop experiments at the facility.

“The details of these kitten experiments keep getting worse and they need to end now. The fact that the USDA has been rounding up pets and other innocent dogs and cats in foreign countries —including at Chinese meat markets condemned by Congress — killing them and feeding them to lab cats back here in the States is simply disgusting and unjustifiable,” Mast said.

Senator Jeff Merkley of Oregon said that the experiments were “deeply disturbing.”

We can advance scientific discovery while treating animals humanely, and American taxpayers have every right to expect our government will meet that standard,” the senator said in a statement.

According to the report, the USDA has been breeding kittens at the lab for nearly 40 years, where they infect the animals with diseases only to euthanize and incinerate them weeks later.

Jim Keen, a former USDA scientist turned whistleblower, said that some initial breakthroughs were made in the early days of the experiments but there have been no new findings in the past 20 years.

“It’s crazy. Cannibal cats, cats eating dogs — I don’t see the logic. It’s totally unrelated to the food safety mission,” Keen said. “We shouldn’t be paying for that as taxpayers.”

The report from WCW also suggests that the experiments are now pointless.

“These were all abnormal diets for cats, dogs and mice so likely irrelevant to natural toxoplasmosis biology. Their scientific relevance and justification is questionable, at best, as is their relevance to American public health since we do not consume cats and dogs, and the practice is now outlawed in U.S.,” the report says.

The USDA insists that these experiments, which have cost taxpayers over $22 million, are contributing to “life-saving research.”