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You put that there.

Since there were at least three explosions, but you only need one to destroy a pipeline, it may be that Russia booby-trapped several underwater pipelines that are not under its control.

Ahso. What I meant was that three explosives for two pipelines is one explosive too much. My speculation would be that Russia may have booby-trapped three pipelines with three explosives and when they took them, they places two of them on the same pipeline.

Why placing them at one place and move them later? I can't see circumstantial evidence which could indicate that. To be honest the reason after all is not that coherent. But on the other hand English is just my 2nd language.