Sajid Javid has apologised to 18 members of the Windrush generation who may have been wrongfully removed from the UK or held in immigration detention.
The Home Secretary took the step after a review by his department provided the clearest indication yet of the impact of the scandal.
A trawl of nearly 12,000 historical records has uncovered evidence suggesting 18 people suffered “detriment” because their right to be in the country was not recognised.
The finding relates to individuals whose records indicate that they came to the UK from the Caribbean prior to 1973 and stayed permanently.
But they were unable to demonstrate “continuous residence”, resulting in them being removed or detained in an immigration removal facility or a reporting centre.
Eleven people voluntarily departed, with some having been served with immigration enforcement notices informing them they had no right to be in the UK. None of the 11 were held in detention.
In a further seven cases, people were detained and subsequently released without being removed.
The review also identified 74 individuals who it would appear were either detained or removed because they had lost their entitlement to indefinite leave to remain after leaving the UK for more than two years.
A further 72 people were detained temporarily at the border but allowed to enter.
All of those flagged up by the review will be put in contact with a specialist taskforce set up in response to the crisis and signposted to a compensation scheme.
The Home Office’s initial priority is establishing contact with the 18 cases where the department deems it is “most likely” to have acted wrongfully.
Mr Javid said: “The experiences faced by some members of the Windrush generation are completely unacceptable and I am committed to righting the wrongs of the past.
“I would like to personally apologise to those identified in our review and am committed to providing them with the support and compensation they deserve.”
Ministers faced a furious backlash over the treatment of the Windrush generation – named after a ship that brought migrants to Britain from the Caribbean in 1948.
Commonwealth citizens who arrived before 1973 were automatically granted indefinite leave to remain under the 1971 Immigration Act.
But some have lost their jobs, been denied access to NHS treatment and had their driving licences withdrawn despite living in the UK legally for decades.
The Home Office’s latest review looked at 11,800 cases of Caribbean Commonwealth nationality, born before January 1 1973, who have been removed and/or detained since 2002. Criminal cases were not included.
It found a total of 164 people who were detained or removed who had something on their file indicating they may have been in the UK before January 1 1973.
Mr Javid said: “It is clear from our internal analysis of these that features of individual cases are markedly different.
“The way in which each individual was treated by the department, and the degree of detriment suffered, varied considerably.”
Referring to the 18 priority cases, he said: “These are the people we have so far identified whom we consider are most likely to have suffered detriment because their right to be in the UK was not recognised and therefore where the department is most likely to have acted wrongfully.”
The Windrush failings have been linked to the Tories’ so-called “hostile environment” approach to tackling illegal immigration
But in a letter to Labour MP Yvette Cooper, who chairs the Commons Home Affairs committee, Mr Javid said the new analysis “exposes problems which have happened over many years, under multiple governments”.
Of the 18 cases covered by his apology, four removals and two detentions were before May 2010, when the Conservatives formed the coalition government.
Shadow home secretary Diane Abbott said the apology is “overdue” and “nowhere near good enough”.
Steve Valdez-Symonds, of Amnesty International UK, said: “The Home Secretary’s apology to just 18 individuals is worrying and brings into question whether the Home Office has a realistic grasp on all the people it has wrongly detained and removed following the exposure of its appalling treatment of the Windrush generation.”
Other Home Office figures show 2,272 people were helped to get documentation to prove their right to be in the UK under initial arrangements, while 1,465 have been granted citizenship or documents under the Government’s formal Windrush Scheme.