The Centre for Food Safety said on Wednesday that it’s investigating whether an importer brought in Japanese vegetables in breach of regulations introduced following the 2011 Fukushima nuclear disaster.

The centre said it had marked and sealed the consignment of vegetables to ensure that they do not enter the local market.

In a statement, it said its checks found a packed of Japanese maple from Fukushima, in defiance of a ban on all imports of vegetables, fruits, milk, milk beverages and dried milk from the province.

It also discovered a packet of eggplant from Gunma that was not accompanied by a radiation certificate and exporter certificate, as required under a Food Safety Order introduced by the government last month.

Gunma is one of four prefectures for which imports have to be accompanied by the certificates.

The centre said in a statement that it would “continue to follow up on the incident and take appropriate action, including informing the Japanese authorities concerned of the incident”.

It added: “Prosecution will be instituted against the importer concerned should there be sufficient evidence. The investigation is ongoing.”

The order in question dates back to the 2011 disaster rather than the recent release of treated radioactive water from the stricken Fukushima plant.

The government implemented a separate order on August 24 as Japan began discharging into the Pacific some of the 1.34 million tonnes of waste water that has collected at the Fukushima plant since a tsunami crippled the facility in 2011.

The new rules ban imports of all live, chilled, frozen and dried sea products, sea salt and seaweed from Fukushima, Tokyo, Chiba, Tochigi, Ibaraki, Gunma, Miyagi, Niigata, Nagano and Saitama.