This image provided on July 3, 2020 courtesy of the National Park Rescue charity shows the carcass of one of the many elephants which have died mysteriously in the Okavango Delta in Botswana. Hundreds of elephants have died mysteriously in Botswana's famed Okavango Delta, the wildlife department said on July 2, 2020, ruling out poaching as the tusks were found intact. The landlocked southern African country has the world's largest elephant population, estimated to be around 130,000. (NATIONAL PARK RESCUE / AFP)

GABORONE - Botswana is investigating a growing number of unexplained deaths of elephants, having confirmed 275 had died, up from 154 two weeks ago, the government said on Thursday.

The dead elephants were first spotted months ago in the Okavango Panhandle region, and the authorities say they have since been trying to discover the cause

The dead elephants were first spotted months ago in the Okavango Panhandle region, and the authorities say they have since been trying to discover the cause. Poaching has been ruled out as the cause of death, as the carcasses were found intact.

“Three laboratories in Zimbabwe, South Africa and Canada have been identified to process the samples taken from the dead elephants,” the Ministry of Environment, Natural Resources, Conservation and Tourism said in a statement.

In a report prepared for the government and seen by Reuters, Elephants Without Borders (EWB), a conservation organisation, said that its aerial surveys showed that elephants of all ages appeared to be dying. The group counted 169 dead elephants on May 25, and another 187 on June 14, according to the report.

Map locating the Okovango Delta, released on July 2, 2020. (MAP / AFP)

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The directors of EWB did not immediately respond to phone calls or text messages seeking comment on the report.

“Several live elephants that we observed appeared to be weak, lethargic and emaciated. Some elephants appeared disorientated, had difficulty walking, showed signs of partial paralysis or a limp,” the report said.

“One elephant was observed walking in circles, unable to change direction although being encouraged by other herd members.”

The report said urgent action was needed to establish if the deaths were caused by disease or poisoning.

Africa’s overall elephant population is declining due to poaching, but Botswana, home to almost a third of the continent’s elephants, has seen numbers grow to 130,000 from 80,000 in the late 1990s.

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However, they are seen as a nuisance by some farmers, whose crops have been destroyed.

President Mokgweetsi Masisi lifted a five-year ban on big game hunting in May last year but the hunting season failed to take off in April as global travel restrictions meant hunters from many coronavirus-hit countries could not enter Botswana.