Debris cleanup work by Tokyo Electric Power Co. at the Fukushima No. 1 nuclear plant may have led to the contamination of rice crops in nearby areas, agriculture ministry officials said Monday.

Radioactive cesium exceeding the government limit of 100 becquerels per kilogram was detected in rice crops from Minamisoma, Fukushima Prefecture, last year, including areas located more than 20 km from the crippled nuclear plant.

Farm ministry officials said they could not deny the possibility that radioactive dust was stirred up when Tepco cleaned up debris at the No. 3 reactor last August and that the dust could have made its way north to Minamisoma.

The ministry told Tepco in March to take measures to prevent dust dispersal, according to the officials.

A Tepco spokesman said the company does not deny the possibility that its cleanup work is to blame but added it isn’t clear whether that was the direct cause of the contamination.

The tainted rice was tested by the Fukushima Prefectural Government and never made it to market.