Department of Natural Resources officers put the bear down "to avoid safety issues with other animals, zoo employees, visitors and nearby residents," general manager Bruce Dougan said in a statement.
“This is an unfortunate situation," he said.
“We do find skunks and raccoons who find their way under or over our perimeter fence, but in my 24 years at the zoo, I have never seen a large wild animal enter the facility.”
The incident occurred some time before dawn, said Dougan.
The bear attacked a Reeves Muntjac, also known as a barking deer.