SYDNEY/LONDON/STOCKHOLM/PARIS: Tax authorities in Australia and New Zealand are probing local clients of a Panama-based law firm which is at the centre of a massive data leak for possible tax evasion.

Other jurisdictions are likely to follow suit following the leak over the weekend of details of hundreds of thousands of clients in more than 11.5 million documents from the files of law firm Mossack Fonseca, based in the tax haven of Panama.

The documents are at the centre of an investigation published on Sunday by the International Consortium of Investigative Journalists and more than 100 other news organisations around the globe.

The German newspaper Sueddeutsche Zeitung said it received the huge cache of documents and shared them with the other media outlets.

The leaked "Panama Papers" cover a period over almost 40 years, from 1977 until last December, and allegedly show that some companies domiciled in tax havens were being used for suspected money laundering, arms and drug deals and tax evasion.

The Australian Tax Office (ATO) said it was investigating more than 800 wealthy clients of Mossack Fonseca.

"We have now linked over 120 of them to an associate offshore service provider located in Hong Kong," the Australian tax office said in a statement. It did not name the Hong Kong company.

ATO Deputy Commissioner Michael Cranston said his office was working with the Australian police and the anti-money laundering regulator AUSTRAC to cross-check the data, and some cases may be referred to the Serious Financial Crime Taskforce.

The 800 individuals under investigation include taxpayers who had previously been investigated and others who had reported themselves to the tax office under a voluntary disclosure initiative which allowed people to come forward and avoid steep penalties and criminal charges and has since ended.

However, the ATO said those under investigation also included many taxpayers who had not previously come forward.

New Zealand's tax agency said it was working closely with its tax treaty partners to obtain full details of any New Zealand tax residents who may have been involved in arrangements facilitated by Mossack Fonseca.

The British government on Monday asked for a copy of the leaked data so it could examine the information and act on any possible tax evasion.

The leak could be embarrassing for Prime Minister David Cameron, who has spoken out against tax evasion and tax avoidance.

His late father, Ian Cameron, is mentioned in the Panama Papers, alongside some members of his Conservative Party in the upper house of parliament, former Conservative lawmakers and party donors, British media said. Cameron's office declined to comment.

Indian Prime Minister Narendra Modi's government vowed to crack down on the "menace" of so-called black money as the names of a number of notable Indians were found in the Panama Papers, including Bollywood stars, real estate tycoons, top industrialists, sportspeople, businesspeople and politicians.

French President Francois Hollande promised that the leak would lead to legal proceedings in France.

Hollande said: "All the information revealed will lead to investigations brought by the tax authorities and to legal proceedings" and he thanked "whistleblowers" for bringing the Panama Papers to light.

Swedish tax authorities will also ask news organisations for leaked documents to see if they contain information about tax evasion.

Swedish state television reports that the document includes the names of 400-500 Swedes.

"We will request access to see if these persons have accounted for taxes in Sweden or not. If they haven't we will launch investigations," a spokesman for the tax authorities told Reuters.

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"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 Gerard Ryle, director of the International Consortium of Investigative Journalists.

Britain's Guardian newspaper said the documents showed a network of secret offshore deals and loans worth $2 billion led to close friends of Russian President Vladimir Putin. Reuters could not independently confirm those details.

Kremlin spokesman Dmitry Peskov did not immediately respond to a request for comment from Reuters on Monday.

Last week, Peskov said reports about the financial dealings of concert cellist Sergei Roldugin, a friend of Putin, and other related reports, were part of a politically motivated campaign to discredit Putin ahead of a cycle of elections.

Database 'hack'

The head of Mossack Fonseca has denied any wrongdoing but said his firm had suffered a successful but "limited" hack on its database.

The firm's director, Ramon Fonseca, described the hack and leak as "an international campaign against privacy".

Fonseca, who was up until March a senior government official in Panama, said in a telephone interview with Reuters on Sunday the firm, which specialises in setting up offshore companies, has formed more than 240,000 such companies. The "vast majority" of these have been used for "legitimate purposes", he said.