Tokyo,-- Plutonium has been detected in soil at five locations at the Fukushima No. 1 nuclear power plant, Tokyo Electric Power Co. said in a statement on Monday.

According to Kyodo News Agency, the plutonium detection suggests "certain damage to fuel rods".

Plutonium, a key ingredient in nuclear weapons, is present in the fuel at the complex, which has been leaking radiation for over two weeks.

While noting that the concentration level does not pose a risk to human health, the power company said it will strengthen monitoring in and around the nuclear plant.

Japan's Nuclear Safety Commission (NSC) said on Monday that its biggest concern regarding the elevated radiation levels in the water at the Fukushima No. 1 nuclear power plant's unit 2 was to prevent the tainted water from leaking into underground soils, water and seawater.

Radiation levels of 100,000 times more than water ordinary found in the reactor water were discovered in water on the underground floor of the turbine building at the unit, according to a statement distributed by the commission at a press conference in Tokyo Monday evening.

The commission said the operator should speed up the removal of the tainted stagnant water and be very careful about radiation protection of workers for continued recovery works.

The NSC also urged to carry out underground water samplings and more precise seawater samplings.

Meanwhile, International Atomic Energy Agency (IAEA) Director General Yukiya Amano said on Monday that he believes it will take some time to stabilize the situation at the nuclear plant.

Speaking at a press conference, Amano emphasized that the nuclear crisis is still serious, but he believes that the problem will be solved.

He said that he has proposed a high-level international meeting, possibly in July, to discuss such issues as nuclear power plant safety and lessons learned from Japan's nuclear crisis.