The Government said it will urgently appeal against a court ruling which prevented 25 people being deported to Jamaica after a last-minute legal battle with human rights campaigners.
Officials say those due to be deported are all foreign criminals who committed serious offences.
But campaigners, supported by 150 MPs, say they came to the country as children, are “British in every meaningful way” and some were sentenced for one-time drug offences when they were young.
A chartered deportation flight, which was due to take off from the UK at around 6.30am on Tuesday, went ahead with 17 on board after the Court of Appeal intervened.
Downing Street said 25 were prevented from being deported as a result of the court ruling. Originally around 50 were expected to be on board.
The flight follows news of a leaked report commissioned by ministers in the wake of the Windrush scandal which warned the Government that the deportation policy should be reconsidered in all but the “most severe cases”, particularly for those who came to the UK as children.
On Tuesday the Prime Minister’s official spokesman said: “There are 25 foreign national offenders who the court ruled could not be removed and are therefore still in the country.
“The offences which these people were responsible for include one manslaughter, one firearms offence, seven violent offences, two which are in the category of rape or sexual offences and 14 drugs offences.
“We bitterly regret this decision which prevents the removal from our country of foreign criminals convicted of rape, manslaughter, sexual attacks, violence and drugs crimes which spread misery across our communities.
“The legal process for removing these offenders, which has included repeated appeals and judicial reviews, has already cost the British public tens of thousands of pounds.
“The taxpayer will now be left with an even bigger bill and the prospect of convicts who are considered to pose a threat to the UK being granted bail while this matter is resolved.
“We make no apology whatsoever for seeking to remove serious foreign national offenders and will be urgently appealing.”
The 17 deported had amassed “sentences of 75 years” between them for offences including rape, possession of firearms, violent offences including actual bodily and grievous bodily harm and the supply of Class A drugs, Downing Street said.
Under the UK Borders Act 2007, the Home Office must make a deportation order where a foreign national has been convicted of an offence and received a custodial sentence of 12 months or more. This is subject to several exceptions, including where to do so would breach someone’s human rights or the UK’s obligations under the Refugee Convention.
The Joint Council for the Welfare of Immigrants (JCWI) said the flight had “forced” families apart, adding that the deportees were “British in every meaningful way and if the law allows those people to be exiled, it needs to change.”
The flight sparked heated scenes in the House of Commons on Monday as Labour MPs pressed the Government on the matter.
A protest outside Downing Street later in the evening ended up with demonstrators blocking the roads around Parliament Square.
Later that night Lady Justice Simler ordered the Home Office not to carry out the scheduled deportation of some people amid concerns that problems with mobile phone signal at the Colnbrook and Harmondsworth centres in Heathrow had prevented them from having adequate access to legal advice while in detention awaiting deportation.
The order was granted without a court hearing after an urgent application on paper by Detention Action.
The Government has already promised to review the judicial review process.
In a sign of why ministers are determined to act, 12 judicial reviews have been lodged in relation to the deportation flight in the past few days.
A senior Tory source said the situation “makes the case perfectly to the public about why such a review is needed and why certain parts of Westminster still haven’t learned the lesson from the 2019 election”.