The BBC and The Guardian last night published details of investigation into 11 million documents leaked from a Panama law firm.
They are among 107 news organisations around the world to have access to the documents which are said to form the biggest ever such leak to the media.
German newspaper Sueddeutsche Zeitung says it received the documents from an anonymous source more than a year ago.
The work was coordinated by the International Consortium of Investigative Journalism, a non-profit organisation based in Washington.
Sueddeutsche Zeitung said the amount of data it obtained is several times larger than a previous cache of offshore data published by WikiLeaks in 2013 that exposed the financial dealings of prominent individuals.
The ICIJ says it includes nearly 40 years of data from a Panama-based law firm, Mossack Fonseca.
According to BBC Panorama the documents show links to 72 current or former heads of state in the data, including dictators accused of looting their own countries.
The BBC said it does not know the identity of the source.
It claims the documents shed light on money laundering, sanctions dodging and tax evasion.
According to The Guardian the leak comprises 2.6 terabytes of data and is bigger than Wikileaks' disclosures to the paper in 2010 or Edward Snowden in 2013.
The Guardian reports that the documents show "a network of secret offshore deals and vast loans worth $2bn has laid a trail to Russia’s president".
The ICIJ also led the investigation into the HSBC files last year, which disclosed tax evasion facilitated by the bank's Swiss subsidiary.