HONG KONG, Sept. 5 (Xinhua) -- The food safety authority of China's Hong Kong Special Administrative Region (HKSAR) said Wednesday it was investigating a case of illegal food import from two Japanese prefectures that were hit by the 2011 Fukushima nuclear disaster.

The Center for Food Safety (CFS) of the HKSAR government's Food and Environmental Hygiene Department said it inspected a consignment of food imported from Japan and found 50 cartons of sweet potato from Chiba Prefecture and 10 cartons of yam from Gunma Prefecture were not accompanied with radiation certificates and exporter certificates issued by the Ministry of Agriculture, Forestry and Fisheries (MAFF) of Japan, breaching the relevant Food Safety Order.

In the wake of the Fukushima nuclear power plant meltdown, the CFS imposed import restrictions on vegetables, fruits and diary products from five Japanese prefectures, Fukushima and nearby Ibaraki, Tochigi, Chiba and Gunma.

According to a Food Safety Order issued in July by the HKSAR government, with effect from July 24, the food import from Ibaraki, Tochigi, Chiba and Gunma into Hong Kong are permitted with conditions, while the import ban on products from Fukushima will remain in force.

According to the Food Safety Order, the import of food from the four prefectures must be accompanied with radiation certificates and exporter certificates issued by the MAFF.