Six Indians have been arrested in the UK on charges of violating immigration rules and face deportation.
They were arrested after UK Border Agency (UKBA) officers numbering about 20, acting on a tip-off, raided two wholesalers at the centre in Hayes Road in Southall in London on Thursday morning.
The UKBA officers arrested five Indian men, aged between 24 and 33, at Jaystar - two of them for illegally entering the UK and the other three for staying in the country after their visas expired, officials said.
The sixth man, a 26-year-old failed asylum seeker, was arrested at A1 Veg Ltd.
Their employers face fines of up to 10,000 pounds per employee unless they can prove they carried out the necessary checks.
The UKBA said that it will take steps to remove all six workers from the country.
UKBA Assistant Director John Lang warned businesses in the area to ensure they checked their staff thoroughly.
"We continue to have success in targeting illegal workers in this area and more of these kinds of operations are planned," he said.
"My message for businesses is that it pays to play by the rules. Check the status of your staff. Employers of illegal migrants can be hit with big fines – but if you deliberately employ an illegal worker you could face criminal prosecution."