Nineteen illegal workers have been arrested following a UK Border Agency raid on a Leicester clothing manufacturer.
The officers went to House of Creation, on Hildyard Road, on Wednesday to question staff about their right to work in the UK.
Officers discovered 19 staff, all Indian nationals, who did not have permission to work in the UK.
Fourteen have been detained while five were released on immigration bail.
The agency said action was being taken to deport the illegal workers from the UK as soon as possible.
The business was issued with an on-the-spot penalty notice for employing illegal workers and could be fined up to £190,000 for employing the workers.
Phil Dyer, assistant director for the UK Border Agency in the East Midlands, said: "Illegal working adversely affects local communities and denies job opportunities to local people.
"Employers are expected to carry out basic checks on identity documents before recruiting new staff."