South Wales Police say anyone caught spraying or writing graffiti "will be dealt with efficiently and appropriately".
Over the last two or three months, the tag SPEC has been sprayed on property across Ely and Canton.
This was a concern to the community and we are glad that the person responsible has apologised and agreed to clean up the damage.
Graffiti is criminal damage, which can affect quality of life, increase fear of crime in some areas and reduce pride in a community. This will not be tolerated.
More top news
Rain in the east will clear through this evening leaving much of the night drier with clearer spells.
Emergency services are being put through their paces in a two-day anti-terror exercise.
Carwyn Jones includes repealing the UK government's new restrictions on public sector strikes in his legislative programme.