Borders police are investigating the seventh vandalism attack on speed cameras in the area in three years.
A camera on the A697 at Rumbletonrig near Greenlaw was damaged at the weekend when a burning tyre was also put round another camera on the road.
Police have appealed for witnesses to either incident to come forward.
Eight cameras were installed on the A697 10 years ago. The other vandal attacks have taken place on the A1 and A68 in the region.