A rural crime team is investigating after graffiti was daubed over the walls of former mine buildings in the Elan Valley.
Police say this incident of 'heritage crime' took place between April and 13 May this year.
More graffiti on the site (Llandrindod, Builth, Rhayader, Presteigne and Knighton Police)
The local police team said: "Rural crime Team are investigating a recent incident of heritage crime (Inc. criminal damage).
"Graffiti has been left on buildings at heritage site - Cwm Elan mines at the Elan Valley estate.
"The damage is believed to have occurred sometime between 1 April and 13 May.
"The site is accessed via a footpath meaning that the offender(s) have had a considerable walk in order to deface and damage the site.”
Anyone with information is asked to email the team at [email protected]"