The 300lb roll bomb was found at the bottom of the cliffs at La Bette Bay, adjacent to Jaonnet Bay.
It was spotted as the search went on for Albie the dog at the start of this week.
Bomb disposal officers confirmed this morning that the fuse was still intact and that it could not be moved safely.
Police cordoned off the area before the controlled explosion around 3pm, with owners of animals in the area notified in advance.
Main picture: the suspected roll bomb on the south coast cliffs.