Japanese media say police have arrested the heads of two construction companies on suspicion of illegally exporting a banned item to North Korea via China.

According to Kyodo News and the Sankei Shimbun Tuesday, Fukuoka and Kumamoto police arrested the two men for allegedly exporting a used power shovel in April last year without obtaining permission from the trade minister. Such exports violate the foreign trade control and customs laws. Police believe the machine's final destination was North Korea.

Kyodo noted that power shovels are designated among items subject to export controls as they could be converted into delivery means and launch pads for ballistic missiles.

The reports added that earlier this month, a trader and his wife in Yamaguchi Prefecture were arrested on suspicion of violating the trade control law by illegally exporting cosmetics to the North, despite a ban on the export of "luxury" items to the country.