A record number of 668 rhinoceros were killed last year in South Africa, according to latest statistics released by the government.

This is a significant 50 percent increase over 2011 and a 5,000 percent increase since 2007, when the number of rhinos poached was 13, reports World Wildlife Fund (WWF), an international conservation group.

A staggering 425 rhinos were poached in the Kruger National Park last year. The North West, KwaZulu-Natal and Limpopo provinces lost a total of 202 rhinos for poaching.

Rhinos are poached due to an increasing demand for their horns in Asia. Rhino horns are touted as prized possessions and command huge prices, as they are mistakenly believed to have medicinal powers that help in curing diseases like cancer.

In December 2012, South Africa and Vietnam (one of the major markets for rhino horns) signed a deal to take joint efforts in curbing poaching and tackling illegal trade of the endangered species.

They also agreed to comply with the Convention on International Trade in Endangered Species of Wild Fauna and Flora (Cites) guidelines.

Even as the nations agreed on a deal to conserve and protect the rhinos, poachers continued to kill the animals. According to the WWF, an additional five rhinos have been killed since the beginning of 2013.

Conservationists have insisted that there is an urgent need to stop illegal trading of rhinos and to ensure that criminals involved in poaching are punished.

"Poachers are stepping up their game and we must do the same. We need to increase protection for rangers on the frontlines and curb the demand for rhino horn in consumer countries to stop this heinous wildlife crime," Matthew Lewis, Senior Program Officer, African Species, Species Conservation Program, was quoted as saying by the WWF.