Pubs and shops have been warned that con-artists are using counterfeit Scottish £20 notes.
Businesses in Leicester's West End say they have been warned by their local banks there is a large number of dud Scottish £20 notes in circulation in the area.
It is thought the fraudsters believe shop assistants and bar workers are more likely to fall for the trick because they are not familiar with the look and feel of the notes.
The warning was issued to a number of businesses in the Narborough Road and Braunstone Gate area last week.
Businesses are being urged to use basic UV lamps or marker pen kits to spot the fakes.
Similar warnings over counterfeit notes and even £1 coins have been issued in the past and the offence linked to organised crime gangs.
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One convenience store owner said: "My bank told me the other day that there is a large number of these notes in circulation in this area at the moment and that we should be careful.
"We haven't had anyone try to use one here yet.
"We use a UV pen to check notes, so I am sure we will know when someone tries to use one of these fakes.
"I think it is more likely they will be successful in a bar or a nightclub where perhaps the staff are going to be busier and might not have the time to check properly."
Citywatch – the business equivalent of Neighbourhood Watch – has previously issuing special pens to shops and bars to help them spot duds.
The pens leave a black mark on a fake note but no trace of ink on the real thing.
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Citywatch intelligence officer Graham Collins said: "Fake notes are a national problem.
"I'd guess whoever is doing this is using Scottish notes because they think people in the pubs and shops won't be as familiar with them as they are with English ones.
"We've also heard of people trying to pass counterfeit Euro notes too.
"Bank notes are made from the same kind of paper and people really should be able to tell from the feel of them.
"If they are in any doubt they should check them with the UV kit."
