London, United Kingdom – Huddled together in a cramped cafe near London’s King’s Cross station, four international students spoke of how their lives were devastated by the government’s response to a BBC documentary.

In February 2014, an investigation by the channel’s Panorama programme found a government-approved exam centre helping international students fraudulently pass a mandatory English-language test, known as TOEIC, in exchange for payments of up to $600.

British Prime Minister Theresa May, the then home secretary, responded with a blanket and forceful crackdown on students who had taken the test.

Over the next two years, immigration enforcement officers set about rounding up those accused of violating the terms of their student visas by cheating in the exam.

Within 10 months of the documentary being broadcast, up to 48,000 students were deported, with many others detained in holding centres.

The campaign of arrests and deportation was brought to a halt by a court ruling in March 2016, later reaffirmed on October 25, which found that the government had acted unlawfully, based its response on “hearsay”, and had not established sufficient evidence that the students had passed the tests fraudulently.

But for the students in the central London cafe, the damage was done and their fears of further crackdowns were far from alleviated.

At the Conservative party conference in October, British Home Secretary Amber Rudd promised restrictions to curtail the flow of international students coming into the country.

The students Al Jazeera spoke to warned that their experience gave some indication of how future crackdowns could pan out.

“They didn’t even knock, they just broke the door,” said Sajjad Shohag from Bangladesh, describing the day border officials arrested him.

“I was just in shock, I knew I had done my exam correctly so I didn’t know why they were there.”

“In the van to the detention centre there was a woman who kept asking me who did my test.”

Despite Shohag’s insistence that he had done nothing wrong, he was detained for 70 days in a holding facility, eventually securing release after being added as a dependent on his wife’s visa.

“I’ve done well on the IELTS [another English language test] and have completed a master’s degree in a British university,” Shohag said.

“I have no reason to lie and cheat.”

No means of support

The allegation of visa violations comes with more than just the threat of deportation. Those without valid permission to reside in the UK are left without means to support themselves through work and have to pay for the welfare services they use.

Ravi Aryal, a graduate of Edinburgh’s Heriot-Watt University, was forced to pause his studies when the Home Office accused him of cheating on his English language exam.

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While rejecting the accusation and appealing against the government’s decision to revoke his right of residency, Aryal has found himself with the added burden of paying for NHS treatment that would otherwise have been free.

The recent birth of his daughter has left the student from Nepal with a potential bill of up to $7,000; money he can ill afford as he has no right to work in the country.

“All of my documents were valid and approved by the British government when I applied for my visa … so how am I now supposed to prove that I’m telling the truth and have done nothing wrong?” he asked.

Aryal and the others were confounded by the lack of recourse they had to challenge the government’s assertion that they had acted fraudulently.

The men explained that while some of those accused were given the right to challenge the accusation inside the UK, they are being forced to appeal from outside the country after deportation.

‘Appeasing lunatics’

The tens of thousands affected by accusations of fraud in exams represent just one segment of the total number of students detained and deported. Al Jazeera spoke to one man who had followed the correct procedure in applying to remain in the UK following the completion of his PhD but was arrested, detained and deported regardless.

Paul Hamilton had just finished his doctoral studies on Shakespeare at the University of Birmingham when he applied to extend his residency in the UK.

The US citizen described what happened next in a post published on his personal blog.

After going to answer an unexpected knock on the door, a border official told Hamilton that his application to stay in the UK had been rejected and he would have to get dressed, pack his bags, and come with them.

The original detention order, seen by Al Jazeera, states that Hamilton’s arrest was necessary as he did not “have enough close ties” to make it likely that he would stay in one place.

But Hamilton describes the reason given as “absurd”. He had spent years at the address and had strong ties to the area.

So you will never know your application has been rejected until the police knock on your door Paul Hamilton

Hamilton explained in the blog post that his detention was made possible by a provision in the British Immigration act of 2014. The law allowed officials to detain applicants for residency in the UK even if they had followed all the correct procedures, provided officials suspected a person may flee.

“[The] new law combines in one absolute ‘decision’ the rejection of an application and the order to arrest, while, at the same time, removing judicial oversight,” Hamilton wrote.

“So you will never know your application has been rejected until the police knock on your door.”

Hamilton told Al Jazeera that a climate of fear surrounding immigrants had created the context in which “stupid” decisions were being made.

“What has happened is that the system of checks and balances has been destroyed,” Hamilton said.

“I think most people can understand that you should never be arrested if you have done nothing wrong,”

“What has happened is that an extra-judicial prison system has been created in the UK, it is justified entirely by a manufactured threat that leads people to make stupid decisions.”

“I suppose many will be cheering what they are doing, but it is irrational and undemocratic.”

Media silence

Ian Dunt, who has written extensively on the TOEIC scandal for Politics.co.uk, shared the assessement that harsher measures against foreign students stemmed from anti-immigrant sentiment.

Dunt told Al Jazeera that media outlets were failing to hold politicians to account for policies that required further scrutiny.

“There has been very little press attention to the story,” Dunt said. “The media never really care when immigrants are having a hard time, so the department was free to do as it pleased. In this case, that meant unfairly detaining and deporting people on the basis of hearsay evidence.

“The TOEIC case is really about what happens when a government department is under incredible political pressure to deliver on an impossible target and is not subject to sufficient scrutiny from the press.”

“The Home Office had to deliver on [former prime minister] David Cameron’s pledge to cut immigration to the ‘tens of thousands’, so it picked on the easiest target – foreign students.”

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‘Short sighted’

There are more than 312,000 non-EU international students in the UK, bringing in up to $17bn in economic benefit to the country.

Attempts to reduce migrant numbers by targeting students could put at risk the UK’s reputation as a leading provider of world-class education, according to leading experts in the sector.

Phil Baty, the editor of the Times Higher Education World University Rankings, told Al Jazeera that he could not comment on individual cases but that restrictions on student visas were sending a “negative message”.

I'll leave here tomorrow if I have to, that's not important … but I want to clear my name and get rid of the allegation that I cheated Syed Waqar Hussain

“The UK’s international students are not only an absolutely vital source of income for UK universities and a great benefit to the wider UK economy, they are a great social and cultural asset too,” Baty said.

“But the anti-immigration rhetoric constantly flowing from the UK Home Office, its refusal to remove international students from net migration figures and from targets to reduce immigration more broadly, and the increasing restrictions on student visas, are all sending out a very negative and unpleasant message to the world – a message that we do not want or welcome international students.”

“This is short-sighted and highly damaging to UK universities and the wider interests of the UK.”

“There is already hard evidence that international students from some key markets, notably India, are turning their back on the UK, and many competitors across the world are welcoming them with open arms. Our status as a top destination for students across the world is diminishing by the day.”

Lobbying politicians

For the students Al Jazeera met in London, regrets about coming to Britain were secondary to immediate concerns. Their priority remained their ongoing legal cases, as well as raising awareness of the issue among parliamentarians.

The men told Al Jazeera that they had gathered cross-party support from MPs and were in the initial stages of a broader campaign to address their grievances.

A group of about 200 students in London are lobbying politicians to take on their cause.

For one of their leaders, a computer science student from Bangladesh called Syed Waqar Hussain, the issue had taken on more importance than just the right to study and reside in Britain.

“I’ll leave here tomorrow if I have to, that’s not important … but I want to clear my name and get rid of the allegation that I cheated,” Hussain said.