Harvard Medical School has been fined $24,000 by the U.S. Department of Agriculture (USDA) for 11 animal welfare violations at its research labs in Massachusetts between 2011 and 2012.

The violations from February 2011 to July 2012 include four monkey deaths and inadequate qualifications and training of the laboratory personnel managing the animals.

One of the monkeys died due to liver failure following an anesthetic overdose. The other two primates perished due to water deprivation, while another strangulated to death while playing with a chain attached to a toy.

Animal rights activists considered the fine as small sum but the university officials at Harvard Medical School deemed it 'appropriate.'

"USDA has resolved its review with an agreement that we feel was appropriate. The leadership of the School cares deeply about upholding exemplary standards of care and attributes these outcomes to the excellent work of those members of our community who took aggressive action to institute rigorous quality improvements that benefit animal safety and welfare," the school said, LA Times reports.

PETA, the animal welfare advocacy group, was unhappy with the disciplinary actions.

"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," the group said,Reuters reports.

All the four monkey deaths and most of the other violations were reported to have occurred at Harvard's New England Primate Research Center in Southborough, Massachusetts. When the violations began to surface, Harvard was forced to implement certain staff and procedural changes at the Center.

The violations also led to the resignation of the Center's director Dr. Fred Wang in March 2012. In April 2013, the school announced its decision to close down the center. The decision was "based on a review of the long-term academic benefits and the financial cost of continuing to operate," the Center said in a statement.

Longwood Medical Area, a smaller facility that includes 45 primates, will continue to operate. The remaining primates "will either be transitioned to other sites, including the other national primate research centers, or be managed at the NEPRC [New England Primate Research Center] in accordance with approved protocols."