An anonymous sign has appeared at a beach warning visitors who take pebbles as keepsakes they will be prosecuted.
The unsigned, laminated sign, appeared on a beach in Amroth, Pembrokeshire, where it warned that "the stones on this beach are part of Amroth’s vital sea defences".
"Removal is a criminal offence," it read.
"Offenders are liable to prosecution.”
The offence falls under the Coastal Protection Act 1949, which leaves offenders liable for a fine for leaving areas exposed to erosion.
It comes after a holidaymaker was forced to drive hundreds of miles to a beach in Cornwall to return pebbles he had taken last year, after a Cornish council threatened court action.
The incident took place in Crackington Haven, Cornwall, where pebble theft has become so common St Gennys Parish Council was forced to put up signs on the beaches warning the practice was illegal.
The poster has had a mixed reaction online, with one resident saying it was difficult to prevent people taking stones from beaches.
Ben Williams wrote: "When your three-year-old little girl wants to keep a pretty little pebble she found, I can't say no.”
A spokesman for Pembrokeshire County Council confirmed while the unsigned poster was not one of theirs, they agreed with the sentiment.
“If everyone started taking pebbles from the beach then we would have a problem. But we have no plans to put up any of our own signs at the moment," he said.