Japan Earthquake 2011

Two New Zealanders sent to Japan to assist in the recovery effort have tested positive for low-levels of radiation.

Exhausted New Zealand search and rescue workers were reunited with their families today, having spent nearly a month involved in rescue efforts first in Christchurch and then Japan.

In the first sign that contamination from Japan's stricken nuclear complex had seeped into the food chain, officials said that radiation levels in spinach and milk from farms near the tsunami-crippled facility exceeded government safety limits.

Military search teams have pulled a young man from a crushed house eight days after an earthquake and tsunami wrecked northeast Japan.

Japan's nuclear safety agency has raised the severity rating of the country's nuclear crisis from Level 4 to Level 5 on a seven-level international scale, putting it on par with the Three Mile Island accident in Pennsylvania in 1979.

Emergency workers frantic to regain control of Japan's dangerously overheated nuclear complex have turned to increasingly elaborate methods to cool nuclear fuel rods at risk of spraying out more radiation.

They risk explosions, fire and an invisible enemy - radiation that could kill quickly or decades later - as they race to avert disaster inside a dark, overheated nuclear plant.

Hundreds of billions of dollars have been poured into Japan's finance sector since Friday's dual quake and tsunami, but stock markets around the world have nose-dived as the wider economic repercussions take shape.