India became a major tea producer after the British set up plantations in the 19th Century to break China's monopoly. The huge estates have traditionally provided for all their workers' needs - but if owners shut them down, thousands can be left without jobs, health care or enough to eat.
Two years ago, Bijiita Ekka was a young teenager enjoying school and playing with other children on the sprawling Bundapani Tea Garden in West Bengal, in the foothills of the Himalayas
The vast, 3,000-acre (1,214-hectare) property had its own hospital, schools and shops and more than 1,000 families were involved in the growing and processing of tea.
Then, in July 2013, the tea garden was shut down. No-one told the workers why - they assume it was not making enough money.
In the first 18 months, 10 people died from malnutrition-related illnesses according to Partha Pratim Sarkar, who runs a tea-worker charity, G-Nesep. The government says it is investigating.
Others, like Bijiita, suffered a different fate.
"We had no money and we had to get money from somewhere," she says. "So my mother took me on a train to Delhi."
There they went to see a labour contractor.
"There were others there like us," says Bijiita. "One woman suggested that it would be terrible and that we should run away now while we had the chance. But we didn't because we had no money."
Bijiita and her mother were locked in an office overnight. Then the pair were separated, and the 14-year-old was taken by train north to Chandigarh, more than 1,000 miles (1,600km) from her home.
"I was terrified because I realised that something really bad was about to happen to me and I didn't know what I could do. I had never felt so scared and lonely," she says, her eyes filling with tears.
What followed was a life of servitude in a military family that treated her like dirt. "I worked all day and everything I did was wrong. They used to scold me and hit me. Even the children would hit me."
She speaks about being constantly hungry, working all the time and being beaten on a daily basis.
Bijiita's ancestors worked as forced labour for British tea merchants, who set up India's north-eastern tea-growing belt in the 19th Century, and imported workers from central regions of the country.
Technically tea workers have been free for decades, but the 1951 Plantation Labour Act, introduced four years after India became independent, remains based on the colonial system. It outlines a duty of care owed by plantation owners to their employees, but at the same time it preserves a system of cradle-to-grave dependency.
And even now, although the minimum wage is 169 rupees ($2.68) a day, tea workers typically only receive 96 rupees ($1.52), the companies arguing that the rest is made up by their welfare package.
In 2007 the UN Children's fund, Unicef, found that hunger, disease and child exploitation were a problem even on apparently successful plantations that sell tea to high-end customers. Now India's tea industry is being scrutinised by the World Bank, the National Human Rights Commission, the UN and other institutions.
"They are cocooned communities," says Unicef's Caroline den Dulk.
"[They] have all their own services, nurseries, schools, health provision - but they are run from a private sector point of view, and the people there are among the most marginalised in India.
"They have fallen off the radar."
The agency has so far failed to gain access to any estates in West Bengal, but it has monitored some in the neighbouring state of Assam - including the Dikom estate, which for many years has sold directly to luxury shops in the West.
Here too, on what many would consider one of the best-run estates in India, it found serious problems. "Probably we were not doing certain things," says estate manager Samar Jyoti Ghaliha, "but now things are changing."
On the wall of his office is a certificate from the London-based Ethical Tea Partnership (ETP), a trade-monitoring organisation whose Trustea initiative aims to ensure workers' rights are not violated.
The Trustea website lists no members from West Bengal, though in the last eight months the 1,000-acre Merry View estate has won certification, and is now producing up to 20% of its tea for export. Seven years ago, like Bundapani, it was at risk of closing.
The tea industry
- Many estates remained under British management after independence in 1947, but by the 1980s they had largely been ceded to Indians
- India's tea industry directly employs more than a million people with many millions more dependent on it for their livelihoods
- It brings in about $3bn a year, with up to a quarter of that coming from exports
- Merry View and Dikom are among only a handful of the more than 1,000 tea estates in the north-east that have opened themselves up to a high level of scrutiny
Today Bundapani has an atmosphere of part post-apocalyptic ghost town and part faded colonial glory.
The once blooming deep green tea bushes are overgrown with weeds.
A post office, a factory and a school are all boarded up and abandoned. The hospital is derelict with broken windows and posters about health care strewn on the floor.
Among those whose health is broken is 28-year-old Krishnan Jhora, who two years ago was fit and working. He's now dangerously thin, and clearly very ill. A skin disease has ravaged his back and his hands and his knees are swollen. His wife Sangiita, 25, has been found a job on another plantation 20 miles away. She has a four-hour commute, and earns 96 rupees per day.
Some welfare is provided by the West Bengal state government, though Partha Pratim Sarkar says it's not enough. He shows me a bag of rice that he says is not fit for human consumption.
But Bijiita is glad to be back home.
One day her mother appeared in Chandigarh, and managed to take her away. She doesn't know exactly how long she spent there, but she knows it was months - and that she was paid nothing.
"When I was working, all I wanted to do was to continue my studies," she says.
"Now I'm at school again and all I want to do is be a teacher."
Suddenly, she grimaces with a memory. "When I was with the family, I tried to read at night. But they caught me and beat me."
She looks down and wipes away a tear. "I can't go back to that life. Please. Never."
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