In the hunt for ivory, 28 endangered elephants have been killed in the Nki and Lobeke national parks in southeast Cameroon in recent weeks, the conservation organization World Wild Life (WWF) reported on Wednesday.

Ivory sells for hundreds of dollars per kilogram on the black market. Most is smuggled to Asia, especially China, to be carved into jewelry and ornaments. As the demand rises, poachers have drastically reduced the population of Africa's forest elephants by 62 percent over the last decade, putting the species on track for extinction, conservationists warn.

"Elephants in these two protected areas in the Congo Basin are facing a threat to their existence," said Zacharie Nzooh, WWF Cameroon representative in the East Region, according to Reuters.

Nzooh said that between Feb. 10 and March 1, WWF found the carcasses of 23 elephants, stripped of their tusks, deep in the Nki national park. A further five were found without their tusks in the Lobeke national park, further to the east.

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) banned the international trade in ivory in 1989. However, there are still some thriving but unregulated domestic ivory markets in a number of countries, which fuel an illegal international trade, the WWF said. Poaching to meet growing demand from affluent Asian countries is driving up the rate of poaching. In some countries, political unrest contributes to elephant poaching.

Around 200 elephants in the Bouba Ndjida National Park were slaughtered by poachers in 2012. Savannah elephants were a popular target before but now poachers are targeting the endangered forest elephants as well. They are the largest mammals alive today and weigh up to eight tons.

Thai Prime Minister Yingluck Shinawatra said at the CITES conference last week that Thailand pledges to start a legislative process to end ivory trade in the country. Ending ivory trade in Thailand - currently the world's largest unregulated ivory market - will go a long way in stemming a global poaching crisis that is leading to the slaughter of tens of thousands of elephants each year and fuelling a global criminal trade in animal parts.