ALERT! Radiaton Level at Fukushima Reactor Increasing

The radiation level at the Fukushima Daiichi nuclear power station is at its highest since the 2011 meltdown.

Latest readings released by Tokyo Electric Power (Tepco), operator of the disaster-hit power plant, revealed that nuclear reactor No 2. reached as high as 530 sieverts an hour, an obviously bigger number compared to the previous record of 73 sieverts per hour. This suggests that melted fuel has escaped the pressure vessel.

Forbes reported that 530 sieverts could kill a person if exposed, and that only one sievert is enough to result in infertility, loss of hair and cataracts.

The Fukushima nuclear accident occurred in 2011 after a 15-meter tsunami disabled the power supply, cooling three Fukushima Daiichi nuclear reactors, World Nuclear Association notes. It's currently known as the worst nuclear accident following Chernobyl.

Tepco also released photos inside of the disaster-hit power plant. The photos reveal black mass deposits suspected to be melted fuel and a collapsed metal grating, which has a one-meter-wide hole.

"It may have been caused by nuclear fuel that would have melted and made a hole in the vessel, but it is only a hypothesis at this stage," Tepco's spokesman Tatsuhiro Yamagishi told AFP. "We believe the captured images offer very useful information, but we still need to investigate given that it is very difficult to assume the actual condition inside."

Japan Times said that if the black mass deposits are proven to be melted fuel, it would be the first time the utility has found any of it at the three reactors that suffered core meltdowns.

Tepco is planning to operate a robot inside the power plant to track the situation of the damaged reactor and remove fuel debris. However, due to the extremely high level of radiation, the robot might not be able to withstand it longer than planned.