Genetic mutations have been found in 3 generations of butterflies near the crippled Fukushima nuclear plant in Japan.

Scientists now fear the radiation could affect other species.

Around 12% of the butterflies that were exposed to nuclear fallout had abnormalities including smaller wings and damaged eyes.

The insects were mated in a laboratory outside the fallout zone.

18% of their offspring displayed similar problems.

That figure rose to 34% in the 3rd generation of butterflies even though one parent from each coupling was from an unaffected population.

The tsunami of March 2011 knocked out cooling systems at the Fukushima nuclear plant causing a meltdown in the worst world atomic disaster for 25 years.