It was the second time in five months that a chimp has escaped from the Michale E. Keeling Center for Comparative Medicine and Research.
In November, a 17-year-old chimpanzee named Jake escaped from his enclosure and had to be sedated after a search lasting several hours on the 381-acre property. Jake was returned safely to his enclosed area.
The animal rights group People for the Ethical Treatment of Animals has filed a formal complaint with the U.S. Department of Agriculture, alleging failure to ensure structurally sound housing and qualified personnel to care for the animals.
"Chimpanzees are intelligent, sensitive, and resourceful -- they shouldn't be incarcerated in laboratories in the first place," said Debra Durham, a PETA primate specialist. "Research on chimpanzees is banned in many countries. The very least that this laboratory can do is ensure that these animals have safe living spaces."
Christian Abee, director of the center, said standard operating procedures were followed after the escape.
"A chimpanzee escape is an extraordinarily rare event in most circumstances," he said. "We are taking statements to determine what happened."
Counselors will be available at the center for the center's 120 employees.
"A tragic event of this type takes its toll on our caregivers," Abee said.
The police department will investigate the incident, standard procedure when an officer discharges a weapon.