A 12-year-old boy carrying a drug bong was stopped by security guards in Asda at Newton Abbot on Saturday, traders in the town report.
The boy was stopped on suspicion of shoplifting goods worth £15.
But when he was asked to turn out the contents of his backpack staff were shocked to find the boy had a bong and grinder, commonly used for cannabis smoking.
One trader said: "Everybody in Asda and all 50 stores in the town centre who are linked up to the Shopwatch security radio heard about it.
"The security guards were shocked because this boy turned out to be only 12 years old and he was obviously smoking pot.
"How many other kids are out there doing the same? That's my real concern."
