Figures from the South African government suggest a substantial increase in rhinoceros poaching in 2012. Most of the animals were killed in the Kruger national park, which is the biggest wildlife reserve in the country.
Around three quarters of the world's rhinoceros population of around 28,000 animals live in South Africa.
668 rhinoceros were killed for their horns in South Africa in 2012. This is almost 50% more than were killed in 2011.
Experts say that demad for rhino horn is growing in countries like China and Vietnam where some people believe it to be a medicine.
Some people in Asian countries like China and Vietnam believe that rhino horn can help to treat diseases like cancer. There is no scientific proof that it works as a medicine.
Rhino horn is sold in countries like China and Vietnam for approximately $65,000 per kg, which makes it very profitable for poachers to kill rhinos for their horns.
Around 2,200 rhinos live in India in the Kaziranga range. Poaching rhinos is also a problem there, where in 2012 900 armed rangers and guards were unable to prevent 18 animals from being killed, compared to 8 in 2011.
The South African government have been trying to fight the poachers with soldiers and surveillance aircraft, but the poachers seem to be winning.
Figures suggest that the poaching of rhinoceros for their horns in South Africa increased substantially in 2012.
The poaching of rhinoceros in South Africa could lead to a population decline.
The animals bleed to death once the horns have been hacked off.
Poaching: The unlawful taking of wild animals or plants