Home Office arrests and aims to deport dozens of people found to be working unlawfully in the UK following huge raid

I'm with more than 100 immigration enforcement and local police officers, hurtling towards a massive construction site a few miles from town.

Their sirens are switched off to avoid detection as our convoy of vehicles pulls up at the warehouse.

Following a months-long investigation, the Home Office has gathered intelligence that indicates people are working at the facility illegally.

Inside, officers quickly start rounding up labourers and begin their inquiries. Names, dates of birth and nationalities are cross-referenced with the Home Office’s system via an app. It’s clear many of those being questioned aren’t supposed to be here.

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One person admits to entering the country in a lorry back in 2003. Others came in lawfully in recent years – but have since overstayed their visas.

As officers make arrests, the suspected rule-breakers frantically plead their innocence, whilst local subcontractors insist their employees are allowed to work in Britain.

Companies can be fined £45,000 per illegal worker hired and firms flouting the law may face prison.

On the other side of the site, there's a flurry of activity as some staff members attempt to flee the authorities. Dramatic body-worn footage shows police apprehending them.

"There was a couple who tried to escape, who we caught and arrested," I'm told by Richard Johnson, Immigration Compliance and Enforcement lead for the West of England.

"If you’re working illegally, we’ll find you, and we’ll detain and remove you."

This raid was one of the biggest of its kind, but there have been 11,000 such operations nationally since Labour's general election victory.

In total there have been 8000 arrests – at businesses like car washes, nail salons, barbers, and take away restaurants.

Immigration minister Mike Tapp says cracking down on illegal immigration is a "top priority" for the Government.

These "arrests are really important," he tells me. Those thirty individuals are "undercutting British workers, who should be filling those jobs."

Out of those arrested, 25 were detained pending their removal from the UK. The rest were placed on strict immigration bail, meaning they must report regularly to the Home Office. Most were Indian or Albanian nationals.

I also saw a few people who were initially arrested then later de-arrested. They were let go as they are still awaiting the outcome of their appeal after their visas were curtailed.

Those appeals can take up to two years, and in the meantime they can keep working, albeit with some restrictions.

"Is this evidence the system is broken?" I asked Mike Tapp.

"There's still a long way to go," the Dover and Deal MP acknowledges.

"We inherited an absolute mess and we’re doing our best to fix that. Those fixes don’t happen overnight."

Stats of the 30 arrested, released by the Home Office:

Overstaying their visa - 21

Illegal entry to the UK - 3

Working in breach of visa - 1

Breaching immigration bail - 5