The San Francisco Zoo may be forced to close its elephant exhibits following the death of a second animal in less than two months.

On Thursday, zoo staff found Maybelle, a 10,000-lb. African elephant, still conscious but unresponsive, KPIX-TV reported Friday.

The 43-year-old pachyderm reportedly died after being given pain medication. Doctors say Maybelle had long suffered from arthritis and foot infections, but her death was not anticipated, the report said.

Zoo officials said Maybelle came to San Francisco from Africa at the age of two. Before arriving she appeared in the John Wayne film "Hatari."

Last month, zoo staff had to euthanize Calle, an Asian elephant, because of health problems stemming from degenerative joint disease and a possible relapse of tuberculosis.

Critics say lack of space is just one reason that the zoo is a bad location for such animals.

Maybelle's death has prompted the animal rights group In Defense of Animals to call for the closure of all elephant exhibits.