A mystery over what killed hundreds of elephants in Botswana, which has the world’s biggest population of the animals, remains unsolved with the government ruling out pesticides, agrochemicals and pathogens as possible reasons for their demise.

Tests done on samples that were taken from some of about 300 carcasses found in northwest Botswan

Tests done on samples that were taken from some of about 300 carcasses found in northwest Botswana and sent to laboratories in Zimbabwe and South Africa for examination proved inconclusive.

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“The results received so far do not eliminate poisoning, therefore environmental factors, including naturally occurring toxins, are still being investigated,” Botswana’s environment ministry said in a statement on Friday.

There are about 135,000 elephants in Botswana and they form an important part of the tourism industry which accounts for a fifth of the economy. The positioning of the dead animals’ carcasses indicate they died sudden deaths.

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