With the crippled Fukushima Nuclear power plant in the earthquake-torn Japan being watched closely across the world, there have been mixed developments at the Daiichi plant. While work to prevent a nuclear meltdown has resumed after a day of suspension, a few workers were rushed to hospital after radiation exposure caused skin lesions. Meanwhile, the International Atomic Energy Agency (IAEA) has warned that the overall situation remains of serious concern despite some progress in terms of reconnecting power lines to some reactors.

Early Thursday, Japanese media reported on resumption of work at the Daiichi plant. Quoting the operator of the quake-hit plant, the official Kyodo news agency reported that the efforts to prevent a meltdown resumed at reactor number 3 of the plant.

The decision to resume work in a bid to restore the plant's cooling system was taken after ensuring that it was safe for the workers to return, Kyodo said. Work at Fukushima plant was suspended for a day after black plume of smoke was seen rising from an overheated reactor at the plant.

Meanwhile, reports emerged that three men were hurt by radiation while working at the stricken Fukushima power plant in Japan.

Two workers were reportedly taken to the hospital after skins lesions were seen on their legs, nuclear safety agents informed Thursday. The men were working in the basement of the No. 3 reactor when they were exposed to between 170-180 millisievierts of radiation.

In a briefing on Fukushima Nuclear Accident, Graham Andrew, Special Adviser to the IAEA Director General on Scientific and Technical Affairs said that although there were positive developments, the situation at the damaged plant still remains a serious concern.

There are some positive developments related to the availability of electrical power supply to the Fukushima Daiichi nuclear power plants, although the overall situation remains of serious concern, Andrew said on March 23.

AC power is now available at Units 1, 2 and 4. Power has been restored to some instrumentation in all Units except Unit 3. At Unit 3, the main control room has lighting, but no power to its equipment or instruments. As a positive development instrumentation, as it becomes available, is providing more data that can be assessed by experts, he added.

A brief update on state of Fukushima Daiichi reactors from IAEA follows:

- Japanese authorities today announced a number of developments at Fukushima Daiichi nuclear power plant, where reactor cooling systems were disabled following the massive earthquake and tsunami on 11 March.

- At Units 1, 2, 3, and 4, workers have advanced the restoration of off-site electricity, and the lights are working in Unit 3's main control room.

- Black smoke was seen emerging from the Unit 3 reactor building, spurring the temporary evacuation of workers from Units 3 and 4. The emission of smoke has now decreased significantly.

- Crews continued today to use a concrete pump truck to deliver high volumes of water into the Unit 4 spent fuel pool, where there are concerns of inadequate water coverage over the fuel assemblies.

- At Units 5 and 6, workers have successfully restored off-site power to the reactor, which had previously reached a safe, cold shutdown status.