More than 4 million people, most of them Muslims, await their fate in Assam as India geared up for the release of a controversial citizens’ list today, which could leave them stateless.

For the last four years, residents of Assam have been scrambling to prove their identity in a court-ordered exercise after decades of campaigns by groups complaining about illegal immigrants.

Today, authorities will seal their fate with the release of the final citizenship list. A draft last year left off four million people. Another one lakh people have been added to the list of the excluded in June this year.

Those left off the National Register of Citizens (NRC) face losing their citizenship, being put indefinitely into camps or deported - to the alarm of UN rights experts and activists.

The photo shows a road sign for a new detention centre being built for people who are not included in the NRC in Kadamtola Gopalpur village, in Goalpara district, Guwahati. Photo: AFP

Authorities in Assam in north-eastern India, for decades a hotbed of inter-religious and ethnic tensions, have brought in 19,000 additional security personnel with gatherings banned in some areas including state capital Guwahati. “Cyber units” have been set up to scan social media for dissent.

Assam, an isolated state of 33 million, has long seen large influxes from elsewhere including during British colonial rule and around the 1971 war of independence in neighbouring Bangladesh. Pressure for a lasting solution has been growing for decades from those who see themselves as genuine Assamese.

Critics of Prime Minister Narendra Modi’s Hindunationalist Bharatiya Janata Party (BJP), which also runs Assam, say the NRC process reflects its aim to serve only its co-religionists.

In January, India’s lower house passed legislation that stands to grant citizenship to people who moved to India from Bangladesh, Pakistan and Afghanistan as recently as six years ago -- but not if they are Muslim.

Indian Home Minister Amit Shah, Modi’s right-hand-man, has called for the ejection of “termites” and said before the BJP’s thumping re-election victory in May that it would “run a countrywide campaign to send back the infiltrators”.

A team of United Nations experts, including the special rapporteur for freedom of religion or belief, said in July that the NRC could “exacerbate the xenophobic climate while fueling religious intolerance and discrimination in the country.”

The process to update the register began following an Indian Supreme Court order in 2013, with the state’s nearly 33 million people having to prove that they were Indian nationals prior to March 24, 1971.

The Indian Home Ministry said last week that those who will be excluded from the NRC would not automatically become foreigners and “every individual left out can appeal to the Foreigners’ Tribunals”.

The roughly two million people who are expected to be left off the final NRC register -- although estimates vary -- will have 120 days to appeal at special Foreigners Tribunals, which the government says are being expanded, reports AFP.

The Indian government said it will also help the poor among the excluded with legal assistance to fight their cases. India has set up at least 1,000 Foreigners’ Tribunals to hear disputed cases.

If one loses the case in the tribunal, the person can approach the High Court and then the Supreme Court and none will be sent to detention centres until all legal options are exhausted, reports our New Delhi correspondent citing Indian government sources.

It is unclear what will happen to those ultimately branded as foreigners because India has no treaty with Bangladesh to deport them.

And there are no such facilities in Assam to hold such large number of people. There are only six such detention camps exist in Assam which are holding 1,135 people and running for years now, according to the state government. Ten new such camps have been announced. One with space for 3,000 is being constructed in Goalpara west of Assam’s capital Guwahati.

During his recently concluded Bangladesh visit, Indian External Affairs Minister S Jaishankar assured Dhaka over the issue.

Asked about concerns that some four million Bangla-speaking people are at the risk of losing Indian citizenship as they were left out of the NRC, Jaishankar said, “This is an internal matter of India.”

Foreign Minister AK Abdul Momen later told reporters that India asked Bangladesh not to worry about the NRC issue.

“We said we are already in serious trouble with 1.1 million Rohingyas … They [Jaishankar] said ‘you don’t worry at all about it’,” Momen told some reporters at his ministry office on August 20.

Critics, however, say the whole NRC process is too complex for many people in a poor region where illiteracy is rife and where many lack documentation.

Rights activists say courts will be overwhelmed since the appeal period is short and the number of pleas will be in millions.

“Imagine FTs adjudicating 2-3 million cases and they have been given just 120 days,” Suhas Chakma, director of New Delhi-based Rights and Risks Analysis Group, told Al Jazeera.

Objections were also raised against the Foreigners’ Tribunals. Critics say that tribunal members, who are not judicial persons, can be underqualified and are subject to “performance” targets, and that the entire process has been riddled with inconsistencies and errors.

“We are genuine Indian people. My forefathers were born here in this land,” Saheb Ali, 55, one of those left out of the draft NRC last year, told AFP.

“My mother’s name was included in the voter list of 1966. We have submitted the documents while filing the forms. However, her name is not there in the draft NRC,” said Ali.

Nur Mohammad, 65, for instance, spent almost 10 years in one detention camp until a Supreme Court order saw him released this month.

“I just want to ask them what is my crime? I was born here and lived in Assam all my life,” he said. “I don’t know if my name will be in the NRC or not.”

Media reports say that there have been more than 40 cases of suicide caused by the worry about the NRC.