Mbube the lion died months after fur began shedding from his mane and he became so emaciated his hips protruded from his golden body, animal rights activists argued.

India the tiger died of sepsis, so ravaged by infection that an autopsy uncovered muscles and organs full of pus, activists said.

And Bandit the lemur, according to court testimony, died after the chronic stress of filthy living conditions, social isolation and untreated illnesses prompted him to gnaw off a portion of his body.

Since at least 2016, endangered animals at the Tri-State Zoological Park in Cumberland, Md., were disappearing one by one. What began as a group of nine lions, tigers and lemurs has dwindled to four survivors. Now the roadside zoo with a history of problems must prepare to give up its remaining animals, after U.S. District Judge Paula Xinis said she will rule that the facility violated the Endangered Species Act.

The judge’s decision comes after People for the Ethical Treatment of Animals sued the zoo, asserting that owner Robert Candy harmed and killed the animals by housing them in deplorable conditions without proper food, environmental stimulation or medical care.

Xinis said that the animals that have survived at the zoo have been “really lucky” and that they will “meet the same or similar fate” as others that have died if they are not removed. Lion Peka and tigers Mowgli and Cheyenne remain at the zoo, while a surviving lemur named Alfredo has been moved to another facility.

Candy and his attorney countered that the zoo took good care of the animals and that PETA lied about some of the conditions at the facility.

“Any person of common sense knows that animals (and people) sometimes die despite the best of care,” Candy’s attorneys argued in court filings.

After a six-day trial in U.S. District Court in Greenbelt last month, the judge said she expects to issue a written opinion in the case before Dec. 16, when the zoo and PETA are expected to return to court to discuss a plan that could relocate the surviving big cats to a different facility.

PETA sued under the Endangered Species Act, a 1973 federal law designed to protect threatened plants and animals. The law bans the harm, harassment and killing of animals on the list and has a “citizen suit provision, which allows PETA to get into court directly when other law enforcement agencies are failing to enforce animal protection laws,” said David Perle, a PETA spokesman.

PETA said it had a legal path to sue because the mistreatment of animals frustrated the organization’s welfare mission.

But the zoo had argued in court filings that PETA should not have been able to bring the case unless it showed the zoo’s actions had directly harmed or injured PETA, rather than being allowed to proceed on the claim its mission had been hobbled.

As part of the lawsuit, PETA asked the judge to order the zoo to give up its endangered animals and bar the facility from housing any endangered animals in the future.

The 16-acre Tri-State Zoological Park opened in 2003 and bills itself as “something for the community to share and enjoy for years to come.” In addition to the endangered species central to the lawsuit, the zoo also houses birds, reptiles, pigs, cats and other animals.

At trial, PETA argued that in case after case, Candy recognized animals were ill but delayed getting them medical care. When the zoo finally called for help, PETA attorney Marcos E. Hasbun argued, Candy relied on veterinarians who had little to no experience taking care of lions, tigers and lemurs.

“They waited unfathomable times before they called a vet,” Hasbun said.

PETA said the zoo also allowed animals to live in conditions so unsanitary they became prone to infection or illness.

Video taken from undercover PETA employees and aired during trial showed shelters covered in layers of feces and bowls filled with cloudy water. The kitchen where feedings were prepared was covered in smelly, rotten food, one PETA employee who visited the zoo testified. And India, the tiger, was living in such unclean conditions that flies ate away at her ears, to the point that a vet later thought they had been surgically trimmed.

Candy and his attorney argued that the animals were well cared for and that PETA immediately jumped to “bald” conclusions. Candy’s attorney, Nevin Young, said at trial and in court filings that PETA mischaracterized conditions at the zoo and that the lawsuit was part of an agenda by PETA to “stop zookeeping as we know it.”

Candy noted that a surviving tiger, Cheyenne, is 17 years old and in good health and that the condition of the other tiger, Mowgli, has improved.

The three-year legal battle with PETA is not the first time the zoo has encountered problems, according to court testimony and previous news reports.

In 2006, 100 animals died in a fire in a building near the zoo entrance. That same year, a U.S. Agriculture Department inspector found that enclosures for lions and tigers were so badly constructed that the animals could easily enter areas designated for visitors.

And in 2013, the year the USDA required the zoo to shut down for 45 days, a federal inspector also noted that children were able to reach through bars and pet young tigers.

At a pretrial hearing this summer, Xinis found that the zoo’s failure to provide proper medical care to a tiger named Cayenne harmed her in violation of the Endangered Species Act. Cayenne went into respiratory arrest after the vet hired by the zoo placed her “under anesthesia,” according to Xinis’s summary judgment in favor of PETA.

But the vet did not reverse the anesthesia or have the equipment to give Cayenne intravenous fluids or respiratory support, and the tiger died. Xinis said the zoo knowingly relied on an inexperienced vet who later conceded in depositions that her medical knowledge in caring for lions and tigers “went no further than watching documentaries aired on Animal Planet.”

During the trial in November, a visibly frustrated Xinis reproached the zoo for allowing the same vet to continue to care for the remaining big cats despite the judge’s earlier pretrial findings of harm to one of the tigers.

“These cats go down in the most horrific way,” Xinis said. “It was as if my opinion did not exist.”

Young said the zoo intends to appeal after the written decision is issued, arguing that the judge should not have allowed PETA to sue.

“This was a difficult trial,” Young said, “because of the pretrial ruling by the court which we thought was in error.”

The judge also should not have allowed PETA’s expert to testify but then bar the zoo from bringing forward its expert, Young said.

Justin Jouvenal contributed to this report.

Correction: An earlier version of this story said the trial in U.S. District Court in Greenbelt took place this month. It occurred last month. The story has been updated.

Correction: An earlier version of this story said the trial in U.S. District Court in Greenbelt took place this month. It occurred last month. The story has been updated.