Since 2011, four monkeys have died at a Harvard Medical School research center. Two died of dehydration, another was killed by an overdose, and the fourth strangled to death on a chain hanging in its cage.

As a result of these repeated animal welfare violations, the U.S. Department of Agriculture fined the university $24,000 on Wednesday. The USDA cited Harvard for 11 incidents, including several pointing out that staff members weren’t properly trained to handle the animals, Reuters reports.

The decision to fine the university comes after a probe into primate mistreatment at its research centers in Massachusetts, one of which Harvard already planned to close for financial reasons.

Harvard released a statement agreeing to the fine. "The leadership of the School cares deeply about upholding exemplary standards of care," it said.

But the animal welfare advocacy group PETA worries that the fine isn’t enough to protect the primates. "For an institution that receives $185 million annually in taxpayer funds alone, half of which is used for experiments on animals, a $24,000 fine for years of abusing and neglecting monkeys won't motivate Harvard to do better," a statement said.