(CN) - A massive document leak from a Panama law firm traced $2 billion in questionable deals to Vladimir Putin's closest circle, has citizens of Iceland calling for their prime minister's head, and indicates that the father of British Prime Minister David Cameron ran an offshore fund to duck taxes, European newspapers reported Monday.
The Guardian called it the biggest data leak in history. Twelve national leaders are said to be among those whose secret offshore dealings have been revealed.
The cache of 1.5 million documents , which are still coming, came from Mossack Fonseca, which The Guardian calls the world's fourth-biggest offshore law firm.
Mossack Fonseca confirmed that documents were leaked, and denied that they showed any wrongdoing.
The German newspaper Suddeutsche Zeitung got the documents from an unnamed source, and shared them with the International Consortium of Investigative Journalists, which passed them on to its members, including The Guardian and the BBC.
The documents show that Mossack Fonseca has served as registered agent for more than 200,000 corporations, according to the Guardian's summary. More than half of them are registered in British-administered tax havens, such as the British Virgin Islands, Guernsey, Jersey and the Isle of Man, the newspaper reported.
The revelations about Russian Prime Minister Vladimir Putin are not surprising, as he has been accused repeatedly of accruing billions of dollars through his strong-man rule. The documents should shed light on the money trail, though. A major conduit for Putin's money is said to be his best friend, Sergei Roldugin, a professional cellist.
Public protests were expected today in Iceland, as the documents indicate that Prime Minister Sigmundur David Gunlaugsson failed to declare his offshore accounts.
Iceland's citizens were punished severely by the 2008 financial crisis, which savaged once-prosperous Icelandic banks. Taxes had to be increased severely after the bank failures. Opposition parties on Monday called for a snap election and citizens were expected to hit the streets in protests Monday afternoon.
The documents also indicate that David Cameron's father, Ian Cameron, "ran an offshore fund that avoided ever having to pay tax in Britain by hiring a small army of Bahamas residents - including a part-time bishop - to sign its paperwork," according one of The Guardian's Monday stories.
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