BROOKFIELD, Ill. -- A female African lion named Isis died just two weeks after her mate at Brookfield Zoo in Chicago's western suburbs.
The zoo says 14-year-old Isis was found in her enclosure Monday morning at the bottom of a moat. It looked like she was badly injured in a fall.
The staff had her humanely euthanized on Tuesday.
Just two weeks ago, her mate, Zenda, had to be put down because of age-related conditions.
"The safety and well-being of the animals in our care is our utmost priority," said Bill Zeigler, senior vice president of animal programs. "Although it is unclear what caused her fall, we are reviewing all aspects of this tragic occurrence."
Both Zenda and Isis arrived at the zoo in May 2008 and they were often seen grooming each other and sleeping together, the zoo said.