More than 2,500 documents from the American anti-money laundering unit FinCEN were leaked on Sunday.

The secret documents show how for years banks helped their customers divert and launder suspicious money.

NU.nl answers the most important questions about these FinCEN Files.

What is FinCEN and how were the documents leaked?

FinCEN is an American financial investigation agency charged with combating money laundering.

Banks are required to report suspicious US dollar transactions (including outside the US) by customers.

However, these reports do not necessarily mean that a customer has actually committed a crime.

Banks have an obligation to prevent their customers from laundering money through their services.

In the case of the US dollar, they do this by submitting a so-called Suspicious Activity Reports (SAR) to FinCEN.

The more than 2,500 documents that were leaked on Sunday come from reports made between 2000 and 2017. According to

BBC

News, they are

very well-kept secrets of the international banking sector.

More than a hundred media organizations in more than 88 countries, including

Trouw,

Financieel Dagblad

and research collective Investico, simultaneously published the findings from the documents.

The documents were leaked to news site

Buzzfeed

and then shared with the

International Consortium of Investigative Journalists

(ICIJ).

Which banks are mentioned in the documents?

Almost all major (international) banks are mentioned in the documents.

The banks include HSBC, JP Morgan, Deutsche Bank and Standard Chartered.

The reports are also about thousands of companies spread all over the world.

The United Kingdom is mentioned most often with more than 3,000 companies.

The main conclusions of the reports are about banks that supported fraudulent financial schemes.

Billions of dollars could be laundered and diverted in this way.

For example, HSBC allowed a Ponzi scheme and JP Morgan allowed more than $ 1 billion to be transferred to a company without knowing what that company was doing.

That company turned out to belong to a criminal wanted by the FBI.

Why does ING also appear in the documents?

As far as is known, the Dutch branch of ING is not mentioned in the documents, but the Polish subsidiary ING Bank Slaski is.

That bank is said to have facilitated the laundering of billions of dollars from Russia.

A Russian network would have diverted tens of billions of rubles through so-called mirror trading (buying currency at the same time and reselling it in another).

This money would have been transferred to offshore companies in Panama and the British Virgin Islands.

The two Dutch companies Tristane Capital and Schildershoven Finance are said to have helped as intermediaries.

Previously, according to the FinCEN Files, the companies were at Deutsche Bank, but at the end of 2013 a switch was made to the Polish branch of ING.

Hundreds of millions of suspect dollars would have been diverted by the method of the Russian network.

ING Slaski and ING Group tell the three Dutch media that they cannot respond to individual cases.

The bank does report that it will investigate the reports about mirror trade.

Current and former directors of Schildershoven and Tristane say they do not want to react substantively against the three media.

Panama Papers, Paradise Papers, what make the FinCEN Files special?

Over the past decade, major leaks at banks and governments have embarrassed thousands of businesses and private individuals.

The Paradise Papers (2017) and the Panama Papers (2016), among others, showed how large companies diverted money, usually through empty offshore companies.

The FinCEN Files are different in this regard, because these are leaked documents that come from dozens of banks.

It is therefore not one company that has been mentioned, but thousands of companies around the world.

The 2,500 documents that have now been leaked are just the tip of the iceberg, according to the ICIJ.

The documents provide insight into how banks keep an eye on suspicious money flows.

In addition, it provides an insight into the widespread corruption in the financial market.

At the beginning of this month, FinCEN said it had already been aware of the leaks.

The American organization warned that its publication is prohibited because it could endanger "American national security".

See also: 'Leaked documents show money laundering practices at banks, including at subsidiary ING'