An official from the International Atomic Energy Agency (IAEA) said in December 2008 that safety rules were out of date and strong earthquakes would pose a "serious problem" for nuclear power stations.

The Japanese government pledged to upgrade safety at all of its nuclear plants, but will now face inevitable questions over whether it did enough.

While it responded to the warnings by building an emergency response centre at the Fukushima plant, it was only designed to withstand magnitude 7.0 tremors. Friday's devastating earthquake was a magnitude 9.0 shock.

The news is likely to put further pressure on Japan's Prime Minister, Naoto Kan, who has been criticised for "dithering" over the country's response to the ongoing crisis at the Fukushima nuclear power plant.

Panic started to spread throughout Japan yesterday following the news that a third explosion at the plant might have damaged the protective casing around the reactor core, increasing the threat of radioactive leaks.

I doubt this was actually Japans fault

**** you whale! **** you dolphin!