Radiology and marine experts from Greenpeace said Tuesday that four out of eight samples of various fish obtained last month at five ports in Fukushima Prefecture exceeded the government-set limit of 500 becquerels per kilogram of radiation.

Although fishery cooperatives in Fukushima have halted coastal commercial operations since March 11 and catches from the area are not being sold to retailers, the environmental group urged the government to conduct detailed checks on fish caught off the Fukushima coast to prevent their accidental sale.

A sample of "kuromebaru" rockfish hit 1,053 becquerels per kg, the group said.