Workers trying to restore the Fukushima No. 1 nuclear power plant on Wednesday entered the building of the troubled No. 2 reactor for the first time since it suffered an explosion in the early days of the nuclear crisis.

Plant operator Tokyo Electric Power Co. has already sent workers into the No. 1 reactor building to lay the groundwork for a system to more stably cool the nuclear fuel. Similar work is expected to take place in No. 2's building, such as checking equipment and adjusting or repairing any malfunctioning gauges.

According to the road map drawn up by the utility, it plans to place crippled reactors 1, 2 and 3 into more stable cooling situations by mid-July and put them into cold shutdown by January at the latest.