The suspects, arrested in New York, New Jersey, Virginia and Texas, face possible 20-year prison sentences if convicted, CNN said.
The government statement issued in New York said the defendants arranged to have ivory from the Ivory Coast, Cameroon and Uganda shipped into the United States disguised as wooden snakes, guitars and statues.
The United States banned ivory imports in 1976. Illegal trade in African ivory is seen as a major cause of the decline of elephant populations in Africa.
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