Officials at the Virginia Zoo in Norfolk say an investigation is under way into the death of a 36-year-old, 2-ton white rhino after he was charged by another adult white rhino.

A spokeswoman said the investigation is looking into why the two male rhinos were left in the same enclosure. Typically they are separated.

The investigation will look into why that practice was not followed.

Rufus came to the Virginia Zoo in 1974, making him the longest resident of the zoo.

Rufus died Monday.

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