More than 500 endangered vultures died after ingesting three dead elephants whose carcasses were poisoned by poachers, the Botswana government said in a statement.

The 537 vultures and two tawny eagles were found dead in one of the country’s protected wildlife management areas (WMA) in the eastern Central District. Among the animals killed were 468 white-backed vultures, 28 hooded vultures, 17 white-headed vultures, 14 lappet-faced vultures and 10 cape vultures.

The government suspects poachers who killed three elephants had laced their carcasses with poison.

Conservationists have called the incident one of the largest documented killings of the threatened species.

The government said the mass poisoning was “dangerous and harmful to the environment” and it urged members of the public to “desist from such illegal acts”.

The area has reportedly been decontaminated and samples taken for a forensic laboratory analysis.

Vultures circling a carcass can be seen from miles away, so poachers often poison them to prevent their activity being tracked.

Most of the birds were white-backed vultures, which are classified as “critically endangered” by the International Union for Conservation of Nature.