Specialist officers intend to detonate "a large piece of ordnance" identified at the bottom of the cliffs at La Bette Bay this afternoon (9 June).
There is currently a police cordon in place between Icart on the west side of the cliff path above Jaonnet Bay.
The Explosive Ordnance Disposal team says it is impossible to move the large ordnance found in the area, so they intend to detonate it there this afternoon.
Anyone who lives in the area is advised to bring animals inside and avoid the cliff paths.
Bailiwick Law Enforcement says officers are talking with colleagues across the States about the potential impact.
UPDATE: The piece of ordnance, believed to have been a 300lb roll bomb, has now been safely disposed of.
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