Both Tanchon and KOMID were previously subjected to sanctions under Executive Order 13382 and sanctioned by the U.N.

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The companies that made the list were Korea Mining Development Trading Corporation (KOMID), Korea Ryonbong General Corporation and Tanchon Commercial Bank.

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It also accused Hong Kong Electronics of facilitating the movement of money from Iran to North Korea on behalf of KOMID.

CNN: U.S. puts sanctions on Iran-based company linked to N. Korea