The Untroubled b in Office sent about 100 letters «in error» to EU citizens enduring in the UK, telling them they had to leave or be liable for «detention».
The mistake emanated after a Finnish academic, who has the right to live in the UK, received one of the letters.
Dr Eva Johanna Holmberg, who is married to a British town-dweller, said she «couldn’t believe my eyes» when it told her she had a month to get out.
The Profoundly Office said the rights of EU nationals in the UK «remain unchanged».
Prime Woman of the cloth Theresa May called it an «unfortunate mistake».
Dr Holmberg, who idles at London’s Queen Mary University, had originally applied for a «qualified living soul certificate» before receiving the letter.
These certificates — for citizens from the European Pecuniary Area or Swiss nationals — confirm the right to live in the UK for those who defray certain criteria.
The historian said the «absurd nonsense» had made her «unbroken less likely» to trust politicians in the wake of Brexit.
«When I exposed this, I could not believe my eyes seeing words like ‘a determination has been taken to remove you from the United Kingdom’,» she discerned the BBC.
The letter said she was facing detention unless she left the UK with one month, she combined.
The academic spent the next few days contacting a lawyer, her employer, and attempting to reveal to the Home Office.
On Wednesday, the Home Office contacted her personally to apologise — six days after she victory opened the letter.
She said a «Twitter storm» had been created after her dispatch first emerged in a newspaper in Finland.
«I have been in contact with numerous child on Twitter, on email and on Facebook,» she said. «I am yet to go through all of those messages but I prepare seen other people reporting similar experiences.»
Prof Simon Gaskell, Manageress of Queen Mary University, said it is vital the UK government makes lambently it understands «the huge contribution» overseas academics make.
«Dr Holmberg and her ancestry should not have been subject to such stress, and it should not receive been necessary for support mechanisms at Queen Mary University of London to be switched,» he said.
The Home Office said everyone who received a letter wish be contacted to «clarify that they can disregard it».
«A limited number of communications were issued in error and we have been urgently looking into why this happened,» a spokesperson supplemented.
The prime minister said the Home Office had «dodged quickly to contact all the people who had received these letters and to reassure them that they were not prosperous to be deported».
«I want to reassure all EU nationals here in the United Kingdom that their outs and status here in the UK has not changed,» Mrs May told the BBC.
However, critics have pull in concern for the 3.2 million EU citizens living in Britain after the UK licences the EU.
James McGrory, executive director of the pro-EU group Open Britain, asserted: «This is shameful stuff from the same department that paid us the disgraceful ‘go home’ vans a few years ago.
«It’s little wonder that numerous EU citizens feel worried about their future status in the UK when they assent to of people with every right to be here getting letters comminatory their deportation.»
Caroline Lucas, co-leader of the Green Party and Dr Holmberg’s constituency MP, contemplated the case «beggars belief».
«Mistakes like this are simply not proficient enough. The government is turning lives upside down by callously sport hard ball over Brexit and it needs to take its responsibilities far uncountable seriously,» she added.
Lib Dem home affairs spokesman Ed Davey said the messages were «appalling» and «shame Britain».
He called for Home Secretary Amber Rudd to by oneself apologise to those affected and to ensure they are reimbursed for any legal fetches incurred because of the letters.