Labour has admitted "losing track" of more than 150,000 migrants who have come to the UK on social care visas.
Government ministers have admitted they have "no idea" how many foreign workers were brought in to fill roles the social care system who are still working in the industry.
In another blow to the Home Office, The Telegraph reports it is not even known if they remain in the UK.
In February 2022, following concerns the sector would collapse, care staff were added to the UK’s skilled worker scheme.
The decision meant workers could come to Britain on a health and care visa if they could secure a job with an employer approved by the Home Office.
In the three years that followed, the UK has granted 154,402 visas to migrants providing "caring personal services" in Britain, allowing them to stay here for up to five years at a time.
However, in 2023 the annual total peaked at 107,772 before falling to 9,539 in 2024, when the Conservative government barred people on care visas from bringing family members with them to the UK.
PA | The Home Office
It comes as care minister Stephen Kinnock was responding to a question from Mid Bedfordshire MP Blake Stephenson, who asked for an estimate of the number of people who have entered the UK on a social care work visa who are still working in the sector.
The MP for Aberafan Maesteg responded saying: "The department does not hold data that directly links visa status to ongoing employment in adult social care or residence in the United Kingdom over time.
"As such, it is not possible to estimate the number or proportion of individuals who entered the UK on a social care work visa and who are still in the UK or working in the social care sector.
"Individuals may cease working in the sector for a variety of reasons, for example to return to their country of origin or to switch to another immigration route."
PA | Stephen Kinnock speaking in the House of Commons
Responding to the news, shadow home secretary Chris Philp told The Telegraph: "The revelation that the Labour Government has lost track of those who came here on a social care visa is shocking. This is further evidence of Labour chaos.
"They have lost control of our borders. We need to bring the levels of immigration down significantly and swiftly remove anyone who is breaching the conditions of their visa.
"The only way to do this is to have a binding annual cap on visas, set by Parliament at much lower levels than we have seen in recent years.
"We tabled this proposal in Parliament just a few weeks ago, yet Labour voted against it."
A spokesman from the Home Office told GB News: "This route, which we closed with our Immigration White Paper, was opened under the previous government.
"We also inherited a data system which was not designed to monitor the long-term outcomes of health and care visa holders, including whether they remain in Britain or continue working in the social care sector.
"The number of people who have been returned from this country is up by 11 per cent since the election, including those who have overstayed their visa, a comprehensive plan has been set out in the Immigration White Paper to bring greater order to our system by reducing reliance on overseas labour."