The University of North Alabama Friday announced its mascot lion, Leo III, died Thursday after a brief illness.

Leo III died “peacefully,” the university said, at the George H. Carroll Lion Habitat at the age of 21 and in the presence of attending veterinarians and volunteer caregivers.

“Leo III and his late sister Una were important members of the UNA family for many years. We are greatly saddened by Leo’s passing,” the university said in a statement.

According to the university, Leo III and his sister Una were born Nov. 18, 2002, at a wildlife refuge in New Hampshire.

They flew to UNA when they were six weeks old in a Learjet donated by a UNA supporter. Leo III weighed nine pounds when he arrived on campus. Upon his death, he weighed 500 pounds.

Leo lived in the school’s $1.3 million lion habitat, built in 2002. It has both indoor and outdoor areas for lions, along with a kitchen and service areas for the caretakers.

In 2012, Leo III and Una were ranked No. 1 of the 25 Best Real Animal Mascots in College Football by totalprosports.com, with UNA being the only non-Division I institution to make the list.

Una died in the summer of 2020.