Key PointsNorth Korea carried out an elaborate money laundering scheme for years using a string of shell companies and help from Chinese firms, moving money through prominent banks in New York, according to confidential bank documents reviewed by NBC News.Wire transfers from North Korean-linked firms with opaque ownership sometimes came in bursts, only days or hours apart, and the amounts transferred were in round figures with no clear commercial reasons for the transactions, according to the documents.Graham Barrow, a London-based anti-money laundering expert, said these kinds of...…Key PointsNorth Korea carried out an elaborate money laundering scheme for years using a string of shell companies and help from Chinese firms, moving money through prominent banks in New York, according to confidential bank documents reviewed by NBC News.Wire transfers from North Korean-linked firms with opaque ownership sometimes came in bursts, only days or hours apart, and the amounts transferred were in round figures with no clear commercial reasons for the transactions, according to the documents.Graham Barrow, a London-based anti-money laundering expert, said these kinds of...WW…