The graffiti painted onto the Oamaru entrance sign. Photo: Hamish MacLean

A limestone sign which greets motorists on their way into Oamaru is in the process of being cleaned up after being defaced with profanity laden anti-1080 graffiti.

A Waitaki District Council contractor was called to remove the graffiti on the sign at Oamaru's southern entrance this afternoon.

Council recreation manager Erik van der Spek said the council was informed of the graffiti at 8am.

The graffiti, which read "F*** 1080" for southbound drivers on State Highway 1 and "Ban 1080" for northbound drivers, appeared to be denouncing the Department of Conservation's use of 1080 as pest control.

Anti-1080 protests have been on the rise recently.

At the weekend, anti-1080 protesters locked Auckland Council staff members in the Hunua Ranges Regional Park where a 1080 drop has commenced.