Two rhinos were found shot dead at the Shamwari Game Reserve near Port Elizabeth at the weekend.
Shamwari veterinarian Dr Johan Joubert said on Sunday that the adult white rhino cow and her calf had been shot with a rifle and their horns had been chopped off.
The carcasses were found on Saturday night in the northwest of the reserve, where there is no road access.
Joubert said the poachers appeared to have accessed the area by foot.
“It seems the rhinos were shot about four days ago, but they were not found until now because it is a remote area,” he said.
“The rifle the poachers used was a heavy calibre and it seems they used an axe to remove the horns.
“We have not had any rhinos poached at Shamwari for six to seven years, so this is very upsetting.”
Joubert said it was possible the tragedy was linked to two recent poaching incidents in the region, and that this was being investigated.
On June 21, poachers killed a rhino on the Thorndale Safari Farm in Kirkwood.
Another rhino was killed at the Kragga Kamma Game Park in Port Elizabeth on June 29.
An investigation into the Shamwari incident led by the reserve’s head of security, Rodney Visser, a former colonel in the police organised crime unit, has been launched.
Ten rhinos have now been killed by poachers in the Eastern Cape this year.
Few official national poaching statistics are released now, but 1,028 rhino were slaughtered in South Africa last year.
Eastern Cape acting police commissioner Major-General André Swart confirmed the Shamwari incident and urged reserve owners to be vigilant and check their game regularly.