Police are stepping up patrols at the Dunwich Heath reserve at Minsmere Road after damage was caused to two warning signs on the cliffs there between 6pm on Saturday 27 and 9am on Sunday 28 June.
The two signs were ripped up and destroyed and another sign was moved.
The incident follows other damage to a picnic bench at the same site earlier in June.
And further damage was caused to a picnic table around 10.30pm-11pm on Sunday night, 28 June.
A group of youths were seen in the area at the time - do you know who they are?
Anyone with information about any of these incidents, or those responsible, is asked to call Sgt 702 Willows on 01986 835300.
Alternatively call Crimestoppers, anonymously, on 0800 555 111.
Police Force: Suffolk
Address:
Minsmere Road
Dunwich
Saxmundham
SUFFOLK
IP17
The location of the incident marked on this map is approximate