SYDNEY (AP) - An Australian zoo says four rare white rhinoceroses have died suddenly after displaying mysterious neurological problems such as stumbling.
The Taronga Western Plains Zoo in New South Wales state said in a statement Wednesday said the animals had died recently but did not specify when.
The zoo has begun a veterinary investigation to pinpoint the cause of the deaths and is working with rhino specialists in Africa and North America.
The investigation has ruled out exposure to toxins, bacterial infection, snake venom and organ failure as causes of death. An unknown number of surviving white rhinos have been placed into quarantine.
Zoo general manager Matt Fuller was not immediately available for comment on Wednesday.
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