BISHNUPUR, INDIA (REUTERS) - Three years ago, police in India's north-eastern state of Assam were looking for a woman named Madhumala Das, who had been declared an illegal immigrant by a local tribunal.
When they reached the village of Bishnupur, they picked up 59-year-old Madhubala Mandal, who was lighting a fire outside her bamboo hut one morning in November 2016.
Ms Mandal, a frail, Bengali-speaking woman who is just over four feet tall, spent over two-and-a-half years in a detention centre until she was freed last month following a probe conducted by a new police chief in the area.
In a recent interview in her hut, Mandal said she told the police she was not the person they were looking for, that she was Indian and had documents to prove it. But they did not listen.
Local activists and lawyers say such cases are not uncommon in Assam, where a long-simmering movement against illegal immigrants, particularly Bengali-speaking Muslims, has been fanned by Prime Minister Narendra Modi's Hindu nationalist government. His ruling Bharatiya Janata Party (BJP) also governs Assam.
BJP's campaign against people deemed to be foreigners from Muslim-majority and Bengali-speaking Bangladesh, even if they have lived in India for decades, or were born in India but can't prove it, is about to reach boiling point.
At the end of next month, Assam plans to publish the final version of a register of citizens it has been preparing since 2015.
Hundreds of thousands - perhaps millions - are likely to be left off the list - meaning they will have to prove their citizenship, or risk detention like Ms Mandal.
This is unlikely to lead to immediate mass arrests because detention centres are full, and Bangladesh has not agreed to accept the people identified as "foreigners".
But being a non-citizen carries many penalties, including loss of access to government payments, voting rights, healthcare and state education. People could be quickly marginalised.
And this isn't only an Assam issue.
Last week, Mr Modi's top lieutenant, Home Minister Amit Shah, who has described Assam's illegal immigrants as"termites", said the government intends to go nationwide in identifying and deporting those who don't have the right to stay.
At the same time, the government has been welcoming Hindu, Sikh and Buddhist migrants, making Muslims feel targeted.
Mr Shah said this month that the government wanted to "stop infiltration and push every single infiltrator out of the country", but would welcome Hindu refugees.
WORSE THAN CONVICTS
When she was arrested, Ms Mandal, a Hindu, was taken to a detention centre in the town of Kokrajhar, in western Assam.
A group from India's National Human Rights Commission that visited that centre last year said illegal immigrant detainees there were in some ways "deprived even of the rights of convicted prisoners".
UN experts warned in a statement this month that the citizenship drive in Assam risked rendering millions stateless or in prolonged detention, and that the process "could fuel religious discrimination", adding that the legal system was discriminative and arbitrary.
The office of the chief minister, the highest elected official in Assam, did not respond to questions sent by Reuters on this story.
Mr Ajoy Rai, a local activist who worked with police to secure Ms Mandal's release, said there may be many more wrongly detained people in the state.
"Most people are not literate and don't understand what the documents they have even mean," he said.
"When there are floods or a fire, people lose the documents too."
Assam, one of India's poorest states, is ravaged by floods annually, displacing millions, with this year no exception.
Rights activists and lawyers say Assam's system of 'foreigners tribunals', detention centres and its 'border police' - a unit in charge of checking illegal immigration - is biased against the poor and against Bengali speakers, who are deemed to be from Bangladesh.
Bengali is the second-most widely spoken language in India, after Hindi. The official language in Assam is Assamese.
A review of orders issued in recent years by Assam's tribunals - quasi-judicial bodies set up for illegal immigration cases - shows many people of Bengali descent have been declared foreigners because of discrepancies in their names and other details on identity documents.
The tribunal judges' performance itself, which is evaluated by the government, appears to be at least partly based on the percentage of the people they declare as foreigners, according to their appraisal sheets. Reuters reviewed copies of the appraisal sheets of judges in 79 of Assam's roughly 100 tribunals.
The documents, which evaluate the judges' performance over two years until April 30, 2017, show that a majority of judges who declared less than 10 per cent of all the people they examined as foreigners got a rating of "may be terminated".
Despite criticism of the process, Assam is working on setting up some 200 more foreigner tribunals by Sept 1, growing to around 1,000 eventually, as it scrambles to prepare for the aftermath of the publication of the final register on Aug 31.
Around 245,000 cases are pending at the tribunals, and scores more are likely to be added after the final list is published.
The government has also lowered the eligibility criteria for the post of judges, allowing retired bureaucrats and lawyers with seven years of experience to apply - as opposed to 10 years required earlier.
"It is obvious that these appointments lack judicial independence or adequate separation from the executive, and the judges are being appointed for tribunals with indications that they should lean in favour of declaring people foreigners," said Mr Sanjay Hegde, a senior Supreme Court lawyer in New Delhi.
There is room for appeal against a tribunal decision through the high court in Guwahati, Assam's main city, But that court is swamped with some two dozen new cases of illegal immigration each week, said Mr Hafiz Rashid Ahmed Chaudhry, a senior lawyer in Guwahati.
Mr Santanu Bharali, legal adviser to Assam's chief minister, dismissed criticism that the tribunals were biased or had targets to declare people as foreigners.
He said the judges relied on documents submitted as proof of citizenship and the tribunals' decisions could be appealed.
'CREATE ONE WHOLE TOWN'
Assam is far from ready to deal with the situation if hundreds of thousands of residents are declared illegal.
The six detention centres there are already overcrowded, said Mr Bharali.
They held 1,133 illegal immigrants as of May 25, 2019, the government said earlier this month.
Assam chief of police Kula Saikia told Reuters there was no clarity on what would be done with those who don't make it onto the citizenship register.
He and other officials say they are awaiting orders from India's Supreme Court, which is supervising the process.
"It's impossible" to detain hundreds of thousands of more people, said police chief Bharali. "We will have to create one whole town for these people."
Local activists say the fear of being declared an illegal immigrant has driven at least 25 people to suicide since a draft citizenship list was drawn up in July 2018.
Reuters could not independently verify the claims, and the police have refrained from linking the suicide cases to the citizenship verification process.
In the case of Madhumala Das, she was first declared a foreigner by a tribunal in 1988, and a fresh order was passed in June 2016 that led to Ms Mandal's arrest.
Police said the mistake occurred as there were three women with similar names in Ms Mandal's village.
"They had to follow the tribunal's orders and find the person," said a senior officer at the police station near Ms Mandal's home.
Madhumala Das had died more than a decade earlier. The border police did not know.