Reports from Japan have confirmed that a group of engineers from the Toyko Electricity Power Company (Tepco) have entered one of the reactor buildings at the Fukushima power plant.
The nuclear plant suffered an explosion in the aftermath of the devastating March 11 earthquake, which led to the plant closing down and a leak of radioactive material.
A spokesperson for Tepco is said to have told international press that a group of engineers are entering the stricken facility to install ventilation systems to filter out radiation.
Levels of radiation must be lowered before a new cooling system can be installed.
The news breaks the day after Tepco staff were photographed on their knees apologising to residents displaced by the nuclear disaster.
There is still a 20km evacuation zone around the plant due to the risk of harmful substances.