Faced with the threat of horse-mounted Sudanese elephant poachers armed with machine guns, the central African nation has deployed military helicopters and 600 soldiers to try to protect the park and its animals.

Its decision to call in the army follows a bloody incursion into the park last winter during which poachers from Sudan killed some 300 elephants, or 80 percent of the park's elephant population, within a few weeks.

Armed only with World War One-era rifles, the park's eco-guards were defenceless in the face of the Sudanese 'jandjaweed' poachers who had travelled thousands of miles on horseback to seize the tusks.

The raid left hundreds of elephant corpses in its wake.

Many of the animals' faces had been hacked off and the bodies lay decomposing in a park that used to attract safari tourists in large numbers.

Cameroon says it is determined to make sure such a scene is never repeated.

"With the kind of deployment we have in the park here today, the message is very clear," Brigadier General Martin Tumenta told Reuters during a visit to the park. "Any poacher who finds himself here will simply be destroyed."

Equipped with helicopters, night vision gear, and scores of jeeps, Cameroon's military has set up two garrisons in the park and several camps along Cameroon's border with Chad and the Central African Republic, Tumenta said.

Last winter's massacre followed a record year for elephant poaching in 2011, an illegal trade that has become a multi-billion dollar industry in Africa fuelled by demand for ivory ornaments from China, some of whose citizens are increasingly wealthy.

Ivory sells for about $300 per kg on the black market, according to conservation group TRAFFIC, meaning that an average-sized tusk weighing 6.8 kg can be sold for a small fortune in central Africa, a region plagued by poverty and underdevelopment.

Officials said there was evidence that the Sudanese poachers were on their way back to the park - a territory of lush forests, rivers and hilly plains about the size of Luxembourg - now that the dry season had arrived, making travel easier.

"It is clear we are dealing with a very heavily-armed group of men carrying machine guns and mortars," said Tumenta, saying soldiers had seized some weapons and ivory from a poacher camp in the bush last year.

The World Wildlife Fund has called Cameroon's deployment a "bold and courageous move" to protect the region's dwindling elephant population.

However, local residents said the huge military presence was disturbing.

"It's now very dangerous because of the soldiers who are just everywhere in the bush," said Saidou Sule, a 48-year-old farmer from a village near Garoua, the provincial capital. (Writing by Richard Valdmanis; Editing by Bate Felix and Andrew Osborn)

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