After 43 monkeys escaped from a medical research laboratory, people are being urged to stay in their homes and keep doors and windows locked.

The rhesus macaques escaped from the Alpha Genesis facility in South Carolina on Wednesday after a new employee failed to fully close an enclosure, police said.

The monkeys are females weighing about three kilograms and are so young and small that they have not yet been used for testing, police said.

Alpha Genesis employees “are currently keeping an eye on the primates and are working to attract them with food,” a police statement said.

“They are not infected with any disease. They’re harmless and a little shy,” Yemassee Police Chief Gregory Alexander said Thursday morning.

“Almost no danger to the public”

The company normally handles escape attempts on site, but the monkeys left the site about a mile (1.6 kilometers) from downtown Yemassee, Mr. Alexander said.

He added: “The handlers know them well and can usually get them back with fruit or a small treat.”

But it takes some time to round up the refugees. Alpha Genesis is taking the lead, setting up traps and using thermal imaging cameras to recapture the monkeys as they escape, the chief said.

“There is almost no danger to the public,” he added.

People who live nearby should close their windows and doors so that the monkeys cannot find a place to hide. If they see the primates, they call 911 so company officials and police can capture them.

According to its website, Alpha Genesis makes primates available for research worldwide at its site 50 miles (80 kilometers) northeast of Savannah, Georgia.

The company has yet to comment on the escape.

Facility fined for previous monkey escape

In 2018, federal officials fined Alpha Genesis $12,600 after dozens of primates escaped and for an incident that left several others behind.

There were problems with housing the monkeys.

Officials said 26 primates escaped from the Yemassee facility in 2014 and another 19 escaped in 2016.

The group Stop Animal Exploitation Now sent a letter to the U.S. Department of Agriculture, calling on the agency to immediately send an inspector to the Alpha Genesis facility, conduct a thorough investigation and treat them as repeat offenders. The group was involved in the fine against the company in 2018.

“The apparent negligence that allowed these 40 monkeys to escape not only endangered the safety of the animals, but also endangered the residents of South Carolinians,” Michael Budkie, the group's executive director, said at the time.

In 2018, Alpha Genesis CEO Greg Westergaard confirmed that the company had paid the fine and confirmed that the company had self-reported all incidents, according to an article on the Stop Animal Exploitation Now website.

Since then, Alpha Genesis has passed inspections without any significant complaints and remains accredited by the Association for Assessment and Accreditation of Laboratory Animal Care.

The Telegraph has contacted Alpha Genesis for comment.

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