However, a zoo spokeswoman said while the postmortem examination showed Umoya suffered a fatal attack by another elephant, the exact circumstances remain unknown because no one witnessed the confrontation, The San Diego Union-Tribune reported Wednesday.
Umoya was found dead Nov. 17 with no visible injuries. The spokeswoman said zoo officials do not know which of the other elephant was responsible or what provoked the attack.
She noted such attacks are not uncommon in the wild, and no changes in managing the zoo's elephant herd have been instituted, the newspaper said.
Umoya was born in South Africa and was one of seven elephants delivered to the Safari Park in 2003. The herd includes two of her calves, Phakamile, 4 years, and Emanti, 18 months.
Notable deaths of 2014 [PHOTOS]
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