Activist Jitu Jakeskia describes Dongria Kondh way of life
High in the monsoon mists in eastern India there is place called Golgola where witchdoctors still make sacrifices to the gods and where the tribes believe the hills are sacred, but where they fear their way of life is under threat.
No roads lead to Golgola, only a muddy track through a lush, green valley. On either side rise the Niyamgiri hills, thick with forests - wisps of cloud wreath their slopes and a light, misty drizzle coats everything.
Then you plunge into the jungle. A slippery path snakes through bamboo thickets and under giant jackfruit and mango trees laden with ripe fruit. For two hours you have to climb what looks an impossibly steep slope. In the humid air sweat soon drenches everything.
High on the hillside you pass a pile of stones next to which are several small statues, primitive figures of men and women, their arms outstretched. This is where the Dongria Kondh people pray to their gods before collecting medicinal plants in the forests.
Then come strange wooden structures, smeared with offerings of fruit. There is a sense of magic in the air. The place feels otherworldly. The sound of drums carries through the forest.
And finally you reach Golgola. It's a tiny hamlet in a muddy clearing, with its two lines of long, low-thatched huts, hidden in a high cleft in the hills.
As we entered the village a witchdoctor, swathed in red, was dancing, almost in a trance, swaying in slow circles from house to house. Her hair was long and unkempt, long strings of beads and shells hung heavy round her neck.
On either side she was flanked by an assistant and behind came two young men in white, bowls on their heads were piled with fruits.
In front of each doorway the family of every house handed a small chicken to the witchdoctor. She held it up, reciting prayers to the gods.
Then, in one swift move the bird's head was ripped from its body, its blood mingled with an offering of rice. The drums beat. The witchdoctor danced barefoot, thick mud oozing between her toes.
Looking on were the villagers, all Dongria Kondh people, women with multiple rings in their noses and ears, many of the men slightly tipsy from jackfruit wine.
Just 7,950 Dongria Kondh are left today.
The Dongria have lived in the Niyamgiri hills in a remote part of eastern India's Orissa state for centuries. They survive by gathering fruit, growing small crops of millet and selling jungle plants in the towns at the foot of the hills. The modern world has yet to reach Golgola - there's no electricity, no school, no television, no telephones.
"We get everything from the jungle like the fruits we take to the market. This is like our source of life for our Dongria Kondh peoples," says Jitu Jakeskia, a young Dongria Kondh activist. He's one of the few Dongria to have got a formal education, and he's now fighting to preserve his tribe's way of life.
"We are not paying any money to get these fruits, this is free, it is like paradise for us here."
The Dongria are animists. Every hill is home to its own god.
"Niyam Raja is our supreme god. His name means Lord of Law, he made all things," explains Jitu. "Niyamgiri mountain is the most important place for Dongria Kondh people, it is like Niyam Rajah's temple, that is why our people worship nature, they have to protect nature."
But an arm of the mining giant Vedanta Resources, one of Britain's biggest listed companies, wants the minerals from Niyamgiri hill.
The Vedanta factory needs legal clearance to mine local bauxite
The range is rich in bauxite, from which aluminium is derived. Critics say mining the hills may cause severe environmental damage, and could disrupt the Dongria's way of life.
Sitting outside his hut, Adu made a cutting gesture across his throat when I asked him about Vedanta. "If they come I will take my axe to them," he said.
Just over the hills, Vedanta has already arrived. An Indian subsidiary Vedanta Aluminium Limited has invested $1bn in a giant alumina refinery at Lanjigarh. It's a vast sprawling site right at the foot of Niyamgiri hill. A tangle of pipes, silos and vast processing towers cover around six square kilometres (3.75 miles).
The refinery is losing money. The Orissa government promised Vedanta access to the bauxite in the hills. However mining can't begin until India's Supreme Court has given its clearance. For now Vedanta is bringing in vast quantities of the red bauxite rock by rail and truck from mines elsewhere just to keep the refinery operating way below its full capacity.
Orissa is one of India's poorest states, but also one of the richest in natural resources, so the government is keen to tap its potential.
At the Vedanta factory
"If you compare iron ore, alumina and coal we can say Orissa has about 60 to 70% of the reserves a country like Australia has," says Dr Mukesh Kumar, chief operating officer of Vedanta Aluminium Ltd and head of the Lanjigarh refinery.
"The only problem is they haven't been developed, once we start exploiting these ores, the day is not far away when we will see the same development in Orissa as we see in Australia."
And Vedanta has big plans.
The bauxite in Orissa is extremely high quality which makes it relatively cheap to refine into aluminium. Vedanta wants to expand the site fivefold and make it the largest of its kind in the world.
The main use for the metal is in food wrappings for things like chocolate bars, potato crisps and snack foods. Another big consumer is the auto industry. As India booms so demand is rising fast in the cities that are far from poverty-hit Orissa.
However there are many who are against mining the Niyamgiri hills.
Activist Dhongra Jita Jakeskia says the jungle is like a paradise
India's Wildlife Institute has said that mining threatens an important ecosystem with irreversible changes.
A Supreme Court committee which investigated the project said Vedanta Aluminium violated guidelines in the Forest Conservation Act when it built its refinery and should have its environmental clearance withdrawn.
And Norway's official Council on Ethics, which monitors investments for the country's huge state pension fund, said investing in Vedanta Resources, which has many mining interests, presented "an unacceptable risk of complicity in current and future severe environmental damage and human rights violations".
Norway's government sold all the Vedanta shares it held which were worth $14m.
Vedanta says all the claims are false. There won't be irreversible damage to the environment. It says it will only mine the surface 10-15 metres down in selected areas in the hills and then fill in the holes when it is finished.
"I don't think any plant can have better environmental standards than we have," Dr Mukesh Kumar told me.
"Our approach is first protect the environment, ensure safety, ensure development of the local area, ensure participation of the community. These are our basic four principles, and if we are not able to ensure them then we are not interested in any project."
Vedanta was keen to show us where it has resettled people displaced by its refinery. Just over 100 families are housed in a small village of concrete huts. The firm says it is bringing development and jobs, investing in healthcare and education in the surrounding area.
Children have no formal education
Nearly 2,000 people are employed in the refinery, many from the local community. It has tried to train people in new skills like fish farming and horticulture. And it is bringing electricity to the villages.
"We have converted land into agriculture land, we have brought soil scientists, we have started livelihood programmes," said Dr Kumar. "In the next few years you will see drastic change in the area."
But while we were there around 80 villagers blockaded the refinery gates, refusing to allow trucks to go in. Five hundred families have lost land to the refinery and say they've not had proper compensation.
Vedanta says these claims are false and are made by people wanting more money than they're legally entitled to.
When we visited a village in the shadow of the refinery people told us their fields and homes were illegally seized without consent and police beat up those who protested.
The Supreme Court committee also reported similar claims, saying those who didn't want to move were beaten up, coerced and threatened, and "an atmosphere of fear was created through the hired goons, the police and the administration".
Dr Mukesh Kumar said not a single case had been registered against Vedanta with the local police, adding that it was the government that repossessed land from villagers so Vedanta was not directly involved.
And he said there was no threat to the existence of the Dongria Kondh in the hills.
"There is no question that Dongria community will finish from this place, that is a false rumour that is spread around this area," says Dr Kumar.
"They will be there where they are today. The only thing is that if that area develops they will get better living conditions, because we may develop some roads, some better infrastructure, better communications, better living conditions."
But in Golgola village many of the Dongria Kondh are suspicious of Vedanta. Jitu Jakesika insists they won't let mining happen in their sacred hills without a fight.
"If the Supreme Court will give a decision to allow mining here, all our Dongria Kondh people from children to old women will go to the factory and sleep on the road and say first you will kill us then you can mine, because we cannot live without our mountain," he says.
We watched as the Dongria made a special offering to the gods, the sacrifice of a water buffalo. It was brutal. The animal was tied to a stake. The witchdoctor let out a shriek, and a dozen men set up on the buffalo with sticks and axes.
It bellowed and struggled for its life as they beat it and slashed at it all over. Finally it sank to the ground with a groan. Its head was severed and carried back to the village in triumph.
The way of life of the Dongria is still, in many ways, primitive and harsh. But they fear the sort of development Vedanta wants to bring, as they worry it may mean an end to their ancient way of life.
You can watch Damian Grammaticas' full TV report on BBC News at Ten at 2200BST, Thursday.
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