FRAUDSTERS have conned Glasgow shops by handing over fake £20 notes.
They bought items from stores using the forged Clydesdale Bank notes, leaving the shops with the worthless currency and out of pocket after having given real cash back as change, as well as losing the items the con men "bought".
Most of the incidents took place in Springburn and Robroyston.
Police said the latest incidents were reported on June 7 and 8.
The fake notes all have the serial numbers AD2586899 or ADT671854.
Police are now warning shop staff to be "extra vigilant" when checking bank notes.
Last August the Evening Times reported that fake £20 notes were being used in scam deals, again in the north of the city.
On those occasions counterfeit Royal Bank Of Scotland notes had been used to buy electrical goods from the public, mainly mobile phones and computers.
The items for sale had been advertised in magazines and on the internet.
Genuine Scottish banknotes have a watermark that is hardly visible until it is held up to light.
Each note also has an individual serial number and fluorescent features, which show up only when they are exposed to ultraviolet light.
Bank notes are printed on special paper, which feels rough – not smooth, shiny, limp, oily or waxy.
Metallic thread is embedded in the paper of all bank notes, and appears as silver dashes on the back of the £20 note.
When held up to the light, the metallic thread appears as a continuous dark line.
Police have launched an investigation into the latest incidents and a spokeswoman said: "We are studying closed-circuit television footage in an effort to help track down the fraudsters.
"We would urge people, in particular shop staff, to be extra vigilant."
Anyone with information is asked to call police on 0141 532 2000.