fact-checkedreputable news agencyproofread New images from inside Fukushima reactor spark safety worryFukushima nuclear power plant showed exposed steel bars in the main supporting structure and parts of its thick external concrete wall missing, triggering concerns about its earthquake resistance in case of another major disaster. display('div-gpt-ad-1453799284784-2'); }); >Tokyo Electric Power Company Holdings, has been sending robotic probes inside the Unit 1 primary containment chamber since last year. Based on data collected from earlier probes and simulations, experts have said most of the melted fuel inside Unit 1 fell to the bottom of the primary containment chamber, but some might have even fallen through into the concrete foundation—a situation that makes the already daunting task of decommissioning extremely difficult