Heidi, Germany's Famous Cross-Eyed Opossum, 'Closes Eyes Forever'

"The cross-eyed opossum Heidi has closed her eyes for ever," said the zoo in Leipzig, eastern Germany.

Within moments of the announcement, tributes began flooding into her Facebook page and on Twitter.

The animal, aged three and a half, had been treated for health problems for weeks and zoo officials decided to put her down "to spare her further pain and suffering."

Heidi's distinctive eye problem was thought to be due to a poor diet before she was abandoned in the United States, or because she was overweight, leading to fat deposits behind her eyes.