Vietnam has lost its fight to save its rare Javan rhinoceros population after poachers apparently killed the country's last animal for its horn, pushing one of the world's most endangered species closer to extinction, a conservation group said Tuesday.

Vietnam's Cat Tien National Park has had no sightings, footprints or dung from live rhinos since the last known animal living there was found dead last April, shot through the leg with its horn chopped off, the WWF said. Genetic analysis of rhino feces had confirmed in 2004 that at least two rhinos were living in the park, raising hopes that Vietnam's population might survive.

Only 40 to 60 Javan rhinos now remain in Ujung Kulon National Park in Indonesia. They are the last known living members of the species, with none in captivity.

Vietnam's Javan rhino population had been shrinking for decades as land conversion and a rising local population threatened the animal's habitat, but poaching and a lack of effective park management and patrols hastened the decline, said Christy Williams, coordinator of WWF's Asian Elephant and Rhino Program.

"It appears that protection is not being given a high priority by the Vietnamese government," he said.

[ Video is no longer available. ]

Park director Tran Van Thanh said that while some of his rangers failed to fulfill their duties, it is impossible for them to stop all of the estimated 100,000 people living near the park from hunting exotic animals when the average farmer there earns around 150,000 dong ($7.50) per day.

"We're not trying to avoid our responsibility in the death of the rhinos, but we've done our best to protect them," Thanh said.

Demand for rhino horn has surged in recent years among Vietnamese and Chinese who believe it can cure an array of ailments. Horns can now fetch up to $50,000 per pound (about $100,000 per kilogram), the WWF report said Tuesday. A small amount of ground-up powder can bring hundreds of dollars on the black market. Global demand has also increased in the last four to five years as some people have begun to considerrhino horn a remedy for cancer, Williams said.

WWF, along with the International Rhino Foundation, confirmed that the last rhino had died in Vietnam by collecting and analyzing its feces. Twenty-two of the rhino's dung piles were found in Cat Tien from October 2009 to February 5, 2010, but no dung piles or fresh rhinofootprints were seen in the subsequent nine weeks, the 44-page report said.

Before 1988, the Javan rhino was believed to be extinct from mainland Asia. A small population was then discovered in Vietnam's park, and for the past 20 years, a number of wildlife conservationists have worked closely with the government to try to prevent the species from dying out in Vietnam.

But the rhino's habitat has been cut in half since 1988 to about 74,000 acres (30,000 hectares) today.

South Africa is a prime source country for rhino horns. According to the South African government, a record 333 rhinos were poached in 2010 — a nearly threefold increase from 2009.

In September, Vietnamese officials traveled to South Africa to address the problem, three years after Hanoi recalled a diplomat from its embassy there after she was caught on tape receiving illegal rhino horns. Ha Cong Tuan, an environmental affairs official, called on Vietnamese medical researchers to study what he called the "rumor" that rhino horn cures cancer and then publicize their findings.

The WWF report said Vietnam is on the verge of an "extinction crisis" with several other species — including the saola and the Tonkin snub-nosed monkey — threatened by deforestation, widespread poaching and a "largely uncontrolled" illegal wildlife trade.

Cat Tien was established in 1998 as a composite of three existing protected areas. From 1998 to 2004 WWF invested $6.3 million in the park, with up to $600,000 earmarked for rhino conservation work.

In Hanoi, the Vietnamese capital, 100 grams (about 7 ounces) of crushed rhino horn retail for about 43 million dong ($2,150), with the average prescription costing 200,000 dong ($10), a rhino horn vendor in the city's bustling old quarter said Monday, requesting anonymity because the practice is illegal here.