NEW YORK - After using a string of shell companies and a hand from companies in China, North Korea carried out an elaborate money-laundering scheme by moving the money through prominent banks in the Big Apple based on the confidential bank documents.

Based on the documents which were reviewed by NBC News, the wire transfers done by the North Korean-linked companies with opaque ownership came in bursts at times, with only days or even hours gap on every transaction.

In addition, the amounts transferred were in round figures, but the transactions have no clear commercial reasons.

London-based anti-money laundering expert, Graham Barrow shared that those kinds of transactions are considered 'red flags' as the efforts to hide the source of the illicit cash are present.

The said documents is not just ordinary bank papers as it is considered as a trove of confidential bank documents as it gives you a rare glimpse on how North Korea and other role players move the illicit cash across borders despite the imposed international sanctions that intend to block the access of Pyongyang to the world's financial system.

Over the years, the suspected laundering by North Korea-linked organizations reached already an amount not less than $174.8 million with transactions cleared through banks in the United States which includes Bank of New York Mellon and JPMorgan Chase based on the bank records.

Former Treasury Department official who worked on the North Korean sanctions during the Trump administration. Eric Lorber shared that taking the thing as a whole looks like it is a concerted attack by a number of North Koreans as they access the financial system of the United States over an extended period of time under numerous and different avenues in ways that were fairly sophisticated.

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The documents that leaked is just a piece of the FinCEN Files which is a collaborative project with the International Consortium of Investigative Journalists which includes NBC News, Buzzfeed News alongside not less than 400 other journalists across the globe, CNBC reported.

The collaborative project's group examined a cache of secret suspicious activity reports filed by banks with the Financial Crimes Enforcement Network of the Treasury Department also known as the FinCEN together with other investigative papers.

Moreover, Buzzfeed was the one who obtained the said leaked documents.

While other media organizations and NBC News are preparing to publish stories based on the leaked documents, FinCEN also has an announcement on Wednesday that they are planning for a major overhaul on the anti-money laundering rules of the country.

SARs or the Suspicious Activity Reports are papers filed by banks and other financial institutions in order to alarm the law enforcement department about a potential illegal transaction, but they do not necessarily include the evidence of the legal wrongdoing. The SARs are closely guarded and highly confidential for the banks and authorities responsible for the issue.

According to FinCEN, they condemned the leak of the said documents and they even declined to give out any comment about the content of the suspicious activity related to North Korea and they suggested that about the matter the Justice Department and inspector general of the Treasury should be consulted.

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