Sabatoge is possible though anything significantly damaging is unlikely. IMHO removing significant quantities of highly radioactive material is not possible.
Suppose the goal is not to remove the material, but to simply release it (like with Three Mile island)?
While I wouldn’t think this would be the case in Belgium, at Fukashima they stored the spent fuel (still cooking) in above ground tanks and not just above ground, but elevated tanks. An idea so stupid it could only be the result of arrogance. Rupture the tank and there is no way to contain the coolant. Holes in the ground work, as useful Today as 5,000 years ago.