One of those fun 4-propeller remote control drones was found Wednesday morning on the roof of the Prime Minister's residence and administrative office complex in central Tokyo. It was discovered by a worker giving a tour of the building and it is not known how long it's been up there without being noticed.
Attached to the drone were a small camera and a plastic container bearing a radiation warning symbol. Police say they were able to detect "minute levels" of radiation from the vial and suspect the substance to be cesium. Which isn't difficult to come by in Japan since the mass meltdown and explosions at Fukushima's Daiichi nuclear facility in 2011.
The Abe administration wasted no time in declaring the drone incident to be an act of terrorism, despite police assurances that the "minute levels" of radiation coming from the vial are too low to affect human health. Apparently unaware of the irony of such a statement, Chief Cabinet Secretary Yoshihide Suga announced that the government will tighten security at key facilities while considering legislation to regulate the use of drones. The need for such legislation is now deemed urgent due to concerns about security at the Tokyo Olympics in 2020, when athletes from all over the world will gather to expose themselves to the enhanced levels of radiation the entire region of northeastern Japan has been enjoying ever since the Daiichi disaster. Which the Japanese government does not consider to be in any way terroristic when it is exported in massive amounts to the rest of the world by air and by sea.
Meanwhile, just up the coast in Fukushima, TEPCO has abandoned the second shape-shifting robot it sent into the unit-1 containment after its camera failed, likely due to high radiation levels in one area of the catwalk. While the IRID/TEPCO's latest handout touted unexpectedly low radiation levels for the second robot's inspection of the catwalk, the latest video of that inspection did show a level of 48.2 Sv/h [4,820 Rem/h] following a 16-second gap (from a level of 3.7 Sv/h).
Reporters at the TEPCO press conference complained about the missing material and IRID/TEPCO's refusal to release the entire feed, which the utility claimed as both "trade secrets" and "nuclear security secrets" despite providing no justification to back up those claims. Previous video from the first robot's inspection showed that there is some depth of water in the bottom of the containment below the catwalk, which they say will be inspected by an underwater robot at a later date. It is safe to say that with a nearly 50 Sv/h 'hot area' along the peripheral containment wall outside of the drywell, (the missing footage would confirm just how hot it really is) covered by some depth water, IRID/TEPCO have found at least some of the missing corium from unit-1's melted reactor core. If or how much of the total mass managed to melt through the downcomer vent/s in that area - thus into the basement torus/torus room - remains to be determined.
At any rate, those "nuclear security/trade secrets" inside the unit-1 containment giving off enough radiation from underwater at several meters' distance over just a few minutes to cause very ugly death within hours are probably not going to find their way into a drone-sized vial that would qualify as an actual terrorist attack on the Japanese administration. For now Prime Minister Shinzo Abe can rest assured he is not being exposed to more cesium in a drone vial on his roof than he'd be exposed to during an afternoon picnic almost anywhere in the northern megaburbs of lovely Tokyo.