More than 440 endangered Saiga antelopes were found dead in western Kazakhstan last week, suspected victims of the same epidemic that killed 12,000 animals last year, officials said on Monday.
The horned animals, distinguished for the flexible snout-like noses, originally inhabited a vast territory stretching from Mongolia to Europe.
But they are now listed as a critically endangered species by the World Wildlife Fund, with an estimated population of 50,000.
The 441 animals found dead last week included 364 does and 77 fawns.
"The fallen animals exhibited poisoning symptoms," the Interfax news agency quoted an emergencies ministry official as saying.
The animals appear to have died from an infectious disease called pasteurellosis, the unnamed official said.
The often-deadly infection strikes the lungs and intestines, and needs to be treated with antibiotics.
Kazakh authorities were currently taking land and other samples to help them determine what had caused the latest outbreak, Interfax said.
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