The first images of melted fuel from the crippled Fukushima No. 1 power plant indicate that it did not burn through the pressure vessel of reactor 3, but exited through the holes used to insert the control rods, officials say.

While the landmark robot footage from the primary containment vessel of unit 3 is helping Tokyo Electric grasp the reality of the damaged fuel assemblies, it may also force it to rewrite the road map for decommissioning the meltdown-hit plant.

Tokyo Electric Power Company Holdings Inc., better known as Tepco, sent an underwater robot into reactor 3 earlier this month to confirm its hypothesis that the core — the fuel assemblies in the pressure vessel — broke apart and fell to the bottom, letting molten fuel burn through and drip into the primary containment vessel.