Poachers slaughtered a record 668 rhinos in South Africa last year, up 50 per cent, as demand for their horns continued to surge on the black market in Asia, the government says.
More than three in five of the slaughtered pachyderms were from the vast Kruger National Park, South Africa's largest wildlife reserve and the country's top safari destination.
Five more animals have been killed since the start of the year, according to the environmental affairs ministry.
Poaching-related arrests climbed from 165 in 2010 to 267 in 2012.
South Africa is home to about three-quarters of Africa's 20,000 or so white rhinos and 4800 critically endangered black rhinos.
Authorities have launched inter-linking campaigns to slow the killings.
Soldiers and surveillance aircraft were deployed in the Kruger Park, while stricter criteria for rhino hunting permits sent applications tumbling 60 per cent to 90 in 2012, from 222 a year before.
Rhinos are victims of a booming demand for their horns, which some people in Asia think have medicinal properties. The medical claim is widely discredited.
South Africa and Vietnam last year signed a deal to tackle the trade.
The number of rhinos poached in the country has risen sharply from 13 in 2007 to 448 in 2011.