Updated

Four of seven elephants outfitted with GPS tracking collars have been killed on the forested slopes of Mount Kenya in recent months only a short hike from the rustic cabin where Prince William proposed to Kate Middleton, conservation officials said Tuesday.

Save The Elephants fitted seven animals near Mount Kenya with collars over the last year to track their movements. More than half have been killed, and the group's founder, Iain Douglas-Hamilton, said he's worried about what may be happening to the elephants who aren't collared.

"We've uncovered a poaching crisis near Mount Kenya that we didn't know about before," he said.

Douglas-Hamilton said the mountain's dense forest makes it difficult for rangers to patrol and protect elephants who have not been collared.

Save The Elephants official Lucy King said the group suspects the rise in poaching in northern Kenya is linked to a high demand for ivory in Asia.

"We're seeing a lot of Chinese nationals caught in the airport in Kenya with ivory in their luggage," she said. "We have to assume the Chinese are involved at some level."

Kenya has more than 30,000 elephants, so the deaths of four do not threaten its population.

The first killing came in October, the same month the royal couple traveled to a rustic log cabin where the two fished in a nearby pond and bundled up for chilly nights at high altitude. It's not known publicly if the two saw any elephants on their trip, but one of the four poached beasts died only 5 miles (8 kilometers) from the cabin, King said.

An elephant named Marani was shot to death in October. A second shooting death came in February. Two others were killed last month, including one suspected shooting death and one death caused by a snare.

Douglas-Hamilton described the agony of the last death, after a team member hiked through thick mountain terrain and through two gorges to find the starved corpse.

"She had been snared with a big rope round her leg and was tied to a tree," he said. "In her last days she had thrashed around and flattened the vegetation, but he found her emaciated. She must have died of lack of food and water."

Susie Weeks, who lives near the 17,057-foot (5,199-meter) mountain for her work with The Mount Kenya Trust, said the region is "rife" with snares and traps. She said ivory poaching began on the mountain in 2009 and has steadily increased.

"Although the snares seem to be laid for smaller game, like buffalo, we find dead elephant calves in these brutal and indiscriminate traps, and amputated or snared calves wondering around with serious infections they cannot possibly survive," she said.

Save the Elephants tracks the real-time movements of elephants it outfits with GPS collars, and the beasts' paths are traced on a special Google Earth mapping program. When an elephant stops moving on the map, the conservationists watching the elephants know there is a problem.

King said poachers shot one of the special collars with two AK-47 bullets. She said that suggests the poachers believe the collars increase the chances they might be caught.

Save The Elephants said more ranger patrols and financial support are needed on Mount Kenya to combat the attacks.