The South Korean government has reiterated that no seafood will be imported from the Fukushima region following reports of substantially excessive radioactivity in a fish caught near the crippled nuclear power plant last month.

The Ministry of Oceans and Fisheries offered the reassurance on Wednesday after a report on the detection by Japan’s Kyodo News the same day.

Since September of 2013, South Korea has banned the import of seafood products from Fukushima and seven other Japanese prefectures near the power plant in response to a nuclear meltdown caused by a massive earthquake and tsunami in 2011.

The ministry said that import regulations will be thorough to prevent the domestic distribution of such seafood products that have sparked concern among the public.

According to Kyodo, the Tokyo Electric Power Company announced that a rockfish caught at a port near the Fukushima power plant last month contained 18-thousand becquerels of cesium, 180 times the threshold set by the Japanese government as safe.