Radiology experts from Greenpeace urged the government Wednesday to expand the evacuation zone around the Fukushima No. 1 nuclear plant after they found high levels of radiation outside the 20-km mandatory no-go zone.

Jan van de Putte, the radioactivity safety adviser of the NGO, said the survey, taken on a road between the villages of Iitate and Tsushima in Fukushima Prefecture, saw a radiation level of 100 microsieverts per hour, despite being outside of the evacuation area.

This contrasts with the 7.86 microsieverts per hour measured in Iitate by the Fukushima Prefectural Government on Wednesday afternoon.