A total of 20 defendants are charged in the case, for their alleged involvement in a variety of schemes such as fake online relationships with victims who were asked to ship and receive merchandise purchased with stolen credit cards and banking information.
The six extradited defendants face nine charges in the US state of Mississippi for the alleged activities which began as early as 2001.
“The defendants identified and solicited potential victims through online dating websites and work-at-home opportunities,” the department said in a statement.
They were additionally involved in check scams as well as bank, financial and credit card account fraud.
They are charged with conspiracy to commit mail fraud, wire fraud, bank fraud, conspiracy to commit identity theft, use of unauthorized account access devices, theft of US government funds and conspiracy to commit money laundering.
Three defendants have already been convicted for their roles while six await trial and two remain on the run. The United States is working to extradite three other Nigerians involved in the case.