A record number of illegal worker arrests and raids have been carried out by the Home Office in the past 18 months.
The number of raids has increased by 77% since July 2024, when Labour came to power, which has led to an 83% rise in arrests, according to government figures.
More than 17,400 raids were carried out by the Home Office's immigration enforcement teams on businesses such as nail bars, car washes, barbers and takeaway shops.
This led to more than 12,300 arrests of those attempting to undercut workers and "hide in plain sight", the government said.
The Home Office said it was the highest number of arrests and raids of illegal workers and those enabling illegal working since records began in 2019.
Ministers believe the crackdown will help reduce the pull factors encouraging people to enter the UK illegally and trying to claim asylum.
Home Secretary Shabana Mahmood said: "There is no place for illegal working in our communities.
"That is why we have surged enforcement activity to the highest level in British history so illegal migrants in the black economy have nowhere to hide.
"I will stop at nothing to restore order and control to our borders."
London, the West Midlands and the South West have seen the highest number of illegal working arrests.
More than 2,100 arrests were made in London last year, a 47% rise compared with 2024.
The West Midlands and the South West both had more than 1,100 arrests - a 76% and a 91% rise respectively.
Of the total arrests, 1,726 people have been returned to the countries they came from, up 35% on the 1,283 removed from visits in the previous 18-month period.
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The raids have included officers arresting 13 people at a warehouse in Shoreham-by-Sea, West Sussex, on 25 November, which led to 11 Brazilian and Romanian nationals being detained for removal from the UK.
On 16 December, 30 Indian and Albanian men were arrested at a construction site in Swindon, Wiltshire. Nearly all them were detained for removal.
The record-breaking enforcement action comes just over two months after Ms Mahmood said her department was "not yet fit for purpose".
She said a crackdown on tackling migrants working illegally in the UK was "starting to work" but criticised enforcement of illegal working rules under the previous Conservative government.
Immigration enforcement was given £5m to arrest, detain and remove migrants working illegally, and officers have been wearing body-worn cameras since September to help publicise arrests and prosecutions.
Tighter right-to-work checks have also been introduced so casual, temporary or subcontracted workers are forced to prove their status.
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