Emails, PDF files and other records from the internal database of Mossack Fonseca, a Panama-based law firm. They are said to cover a period from the 1970s to the spring of 2016.
The Panama Papers are said to provide data on around 214,000 offshore companies. The BBC alleges the documents show how the firm has helped clients launder money, dodge sanctions and evade tax. Mossack Fonseca said it had operated “beyond reproach” for 40 years and had never been charged with criminal wrongdoing.
German newspaper Sueddeutsche Zeitung first received the data more than a year ago. It said the information was offered by an anonymous source who requested no cash compensation. The documents were shared with the International Consortium of Investigative Journalists and more than 100 other news organisations.
“I think the leak will prove to be probably the biggest blow the offshore world has ever taken because of the extent of the documents,” said consortium director Gerard Ryle.
The material allegedly shows that some companies domiciled in tax havens were being used for suspected money laundering, arms and drug deals, and tax evasion.
More details are expected soon although the consortium in Washington, said the offshore holdings of 12 current and former world leaders are detailed in the investigation. It said criminals, celebrities, sports stars and businessmen are included.
Former Fine Gael strategist and Rehab chief executive Frank Flannery was named in the documents over a £250,000 deposit in the name of a British Virgin Islands company being used to support his purchase of a house in London.
Mr Flannery said a loan from Bank of Ireland Private Banking paid for the £615,000 house in 1996. He said he had no explanation why he was named in the documents. Anglo Irish Bank’s branch in Austria was among a small number of banks repeatedly recommended by Panama-based law firm Mossack Fonseca to its clients.
Tax avoidance involves companies and people using legal ways and following the rules to reduce their tax bill.
Tax evasion is an offence and involves illegal ways of paying less tax than required. It is claimed the papers show attempts to use offshore companies to conceal the identities of the actual company owners.