A data leak dubbed the Pandora Papers has revealed that powerful billionaires as well as current and former world leaders have been affiliated with companies that use offshore tax havens.

The investigation was carried out by the International Consortium of Investigative Journalists (ICIJ) and a team of 150 news outlets, including the Washington Post.

The 11.9 million documents – the biggest ever data leak – revealed that 35 current and former heads of state as well as more than 330 politicians and public officials from almost 100 countries have assets in offshore accounts, secretive foundations or shell companies.

Offshore accounts are often used to manage large sums of money covertly to hide a person's true wealth or avoid paying taxes.

Finance Is steel a dying industry in Pennsylvania amid Nippon takeover bid?

Similar to the Panama Papers leaks, the documents were reportedly leaked by an anonymous source. It is the biggest leak to date containing information on tax havens.

The Panama Papers came to the public in spring 2016 due to a data leak. They were documents from the Panamanian law firm Mossack Fonseca, which were evaluated by journalists around the world. They found that numerous politicians, athletes and other celebrities had assets in offshore companies.

The revelations put politicians, business people, and celebrities under significant pressure.