Children living outside the zone where residents have been urged to stay indoors following the nuclear accident at the Fukushima Daiichi power plant have not had their thyroids affected by leaked radioactive materials, the government said Friday.

The announcement was based on the government's checkups Thursday on 66 children aged 1 to 15 in Kawamata, Fukushima Prefecture, which is located northwest of the plant and outside the state-set indoor evacuation zone -- within 20 kilometers to 30 km radius of the plant