Police investigating the "unauthorised use" of land next to a graveyard said they have found an object below ground.
Gwent Police added that they are so far unable to identify the nature of the object.
Officers were called to the area next to Christchurch Cemetery in Newport at around 09:45 BST on 27 April.
A "sensitive excavation" has been taking place and metal fencing has been erected around the scene.
Gwent Police said it was working with the Ministry of Justice and Newport council to investigate the matter on the section of undeveloped land.
Supt Vicki Townsend said: "Officers remain at the scene and investigations are continuing."