ST. PAUL (AP) -- A Duluth polar bear who briefly escaped from her exhibit during June flooding is improving after surgery in St. Paul.

Berlin underwent surgery Saturday at the University of Minnesota Veterinary Medical Center.

Lake Superior Zoo veterinarian Louise Beyea says the polar bear had been acting lethargic and vomiting in its new home at Como Park Zoo.

Exploratory stomach surgery revealed a necrotic mass - tissue that has been killed by disease or trauma - and signs of previous abdominal bleeding.

Berlin has been returned to Como Park Zoo and is under observation.

The polar bear and two seals from the Duluth zoo were relocated to Como Park after the flooding damaged their exhibit. No decision has been announced on whether the exhibit will return.