> >The Geneva convention, for starters.
> Is the full statement.
And that statement is wrong, AFAICT; the Geneva Conventions do not address the conduct at issue here, whether “for starters” or otherwise.
They might prohibit somewhat analogous conduct in a very disanalogous context [0] but context and conduct are not orthogonal considerations in law.
[0] or, maybe not; the specific instrument you are probably thinking of is Amended Protocol II to the Convention on Certain Conventional Weapons; it does address booby-traps, but the device at issue here is not a booby-trap as defined in that protocol (not designed to kill or injure).