GROCERY shoppers are being urged to check the validity of their free-range eggs – after crafty customers were spotted sneaking the organic produce into cheaper “value” boxes.

Finsbury Park residents flooded a local web site with complaints about the egg thieves, who they claim have been spotted most recently in the Tesco in Stroud Green Road.

One resident said: “I saw someone swapping the expensive organic free range ones which cost about �3.50 a half dozen into the box of the value 99p battery ones. So if you buy the expensive ones you may well be getting the value ones. I told the supervisor and she said they often catch people doing it.”

Free-range fans are now being warned to check that their eggs carry the correct free-range stamp, a code beginning with 1 UK, before they make a purchase.

A spokesman for Tesco said: “We have not heard any complaints at the store.

“If any customers see this happening, can they please let the store manager know immediately.”