An investigation looks at how some migrants are working illegally in the UK.

Hello, this is the Marketplace Morning Report, and we're live from the BBC World Service.

I'm Leanna Byrne, and a very good morning to you.

A BBC investigation has exposed how Vietnamese migrants in the UK are working illegally in nail bars to avoid detection.

The government says it's ramped up raids since July

with fines for employers reaching $75,000 per worker

for repeat offences.

But it's not stopping everyone.

Here's the BBC's Divya Tower.

So you're working here at the moment.

No, I'm not working.

It's mid-morning in Wales.

Immigration enforcement teams are raiding nail bars where they suspect people are working illegally.

You're working when I came in, you're working on the side this week?

No.

It's on the basis where you tell you at the moment?

I'm arrested.

Yeah.

I'm scared of sight.

Outside, officers are searching for a young Vietnamese woman in a pink track suit.

Minutes earlier, she was giving a customer a pedicure in the busy nail bar,

but ran out the back when the officers entered the shop.

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