South Africa hippo
In total, 109 hippos have been found dead so far Mike Hutchings/Reuters

More than 100 hippopotamuses have died in a possible anthrax outbreak in Namibia, authorities at a national park have announced. All the animals are thought to have died last week in the African nation's remote north-east.

Anthrax, a bacterial disease, is known to kill cattle and even human beings especially in arid conditions. However, the recent incident has baffled authorities as the deaths followed in quick succession.

Images from the Bwabwata National Park show bodies of lifeless hippos in murky waters. Some of the carcasses were partially submerged with only their heads visible above the water.

Namibia's environment ministry said the first dead hippo was spotted on 1 October but dozens of deaths quickly followed. In total, 109 hippos have been found dead so far. The toll is expected to go up as some of the carcasses could have been eaten by crocodiles in the area.

"We first noticed the deaths of 10 hippos last week Sunday, but the number increased during the week. As we speak, the number of deaths is 109. We suspect an anthrax outbreak, but our veterinary team is still to confirm that," said the park's deputy director, Apollinaris Kannyinga, according to the daily Namibian.

Such outbreaks are common in the region, added the official but insisted the disease is unlikely to spread further since the hippos lived in a remote part of the park. Many water buffaloes have also been discovered dead in the same spot but it is yet to be confirmed if they were also killed by the same outbreak. Namibia's north-eastern region, where the park is situated, is sandwiched between Angola and Botswana.

"There's not much we can do. We can't move the wildlife," an environment ministry official Johnson Ndokosho told the National Geographic.

If confirmed, this is likely to be the first anthrax outbreak affecting Namibia that had an estimated population of about 1,300 hippos before the recent deaths. A similar outbreak in 2004 killed up to 200 hippos in Uganda.