Police arrested the former president of a trading company Thursday on suspicion of illegally exporting a freeze dryer that could be converted for biological warfare use to North Korea via a Taiwanese trading house in 2002.

Kim Young Gun, 58, admitted during questioning that he was aware the device could be used by a military-related research institution in North Korea, police said. Kim used to run the Tokyo-based trading house Meisho Yoko.

A joint Yamaguchi and Shimane police task force arrested Kim on suspicion of unauthorized exporting in violation of the foreign trade law.

Kim, a Korean resident of Suginami Ward, Tokyo, allegedly exported the freeze dryer in September 2002 from Yokohama port to North Korea via Taiwan without the required approval of the trade minister.

After a North Korean trading company inquired about the device, Meisho Yoko is believed to have placed an order for it with the Taiwan trading house via a Tokyo-based business partner.

The Taiwan trading house then bought it through a Tokyo-based scientific instrument maker's sales agent based in Taiwan and passed it on to Meisho Yoko.

Police believe the North Korean company that requested the device is closely related to Korea Rungra 888, a North Korean trading house reportedly controlled by Pyongyang leader Kim Jong Il.

Police think Kim used the firm's business partner and the Taiwan trading house to camouflage the transaction and bypass the strict approval process, the sources said.

Meisho Yoko was established in 1990 and exports cars and home appliances to North Korea. It has partners with close ties to the North's military, a credit research agency said.