New Zealand-based foreign trusts have been caught up in the data leak exposing Panamanian law firm Mossack Fonseca's role in providing financial anonymity to the world's rich.
The leaked papers were obtained by German newspaper Suddeutsche Zeitung and shared with the International Consortium of Investigative Journalists (ICIJ).
They show a connection to foreign trusts in New Zealand.
Maltese Energy Minister Konrad Mizzi and the Maltese Prime Minister's Chief of Staff, Keith Schembri, have set up trusts in New Zealand.
One of them, the Rotorua Trust, is operated by a trustee of Mossack Fonseca - it owns only a shell company in Panama. The other, the Haast Trust, appears to own two Panamanian companies.
Read more on the leak
The revelations have caused a political storm in Malta.
Malta Independent columnist Daphne Caruana Galizia first broke news of the Panama firm owned by Mr Mizzi.
She told Nine to Noon the men set up companies in Panama in 2014 and these companies were then further sheltered by trusts in New Zealand, which were established at about the same time.
"They were completely undeclared and they never expected to be discovered," she said.
She said when the men's ownership of the Panamanian companies and New Zealand trusts came to light, seven weeks ago, political controversy erupted in Malta.
Today's data breach leak had further fuelled the controversy, she said.
"There is absolutely no legitimate reason for them to have opened companies in Panama, and over and above that shelter them by secretive New Zealand trusts," she said.
She said the New Zealand trusts added a second layer of secrecy to the Panamanian companies.
Maltese Premier Joseph Muscat has announced there will be an audit of the companies by the Maltese Inland Revenue.
Ms Galizia said there was no way the Maltese Inland Revenue could conduct such an audit on the companies in Malta.
"The reason people open companies in Panama is precisely so that the tax authorities in their home country can not have access to the information.
"And it is the same with New Zealand; New Zealand will disclose to the New Zealand tax authorities, but it will not disclose to foreign tax authorities."
She said it was possible authorities in this country were unaware the two Maltese politicians were politically exposed people (PEPs) and that one was a current minister in an EU member state government.
"It will now be interesting to see how the New Zealand authorities proceed in the light of these investigations," she said.
New Zealand 'soft touch' - ICIJ journalist
ICIJ director Gerard Ryle said New Zealand was a key player in the offshore world.
"I think you'll find that New Zealand plays a very major role here, because certainly a number of the companies end up being owned by New Zealand trusts.
"For quite a long time, Mossack Fonseca had the exclusive rights to set up offshore companies in Niue, they then moved a lot of their companies to Samoa. But you'll find New Zealand is actually a very, very key player in the offshore world."
Mr Ryle said the leaked documents showed a pattern of behaviour.
"As soon as organisations like the OECD or the European Union try to crack down on secrecy or tax evasion, what this world is doing is maneuvering around the new laws that come in, and that is very certainly the pattern we are seeing in the documents.
"As soon as a new tax is brought in in Europe but there's a loophole that allows individuals to avoid tax, by becoming a corporation in the British Virgin islands for instance, then that's what's happening."
New Zealand was a soft touch, he said.
"That's something that is outside the documents. I know that from personal research into this area.
"New Zealand is vulnerable. It's very easy to set up an offshore company in New Zealand and what's good about New Zealand from the offshore perspective is that it's a first world country, people don't think that anything nefarious will be happening if you're doing it through New Zealand - so it's a perfect cover."
Mr Kyle said the investigation was the biggest in journalistic history.
"We've got 370 journalists in more than 70 countries who have worked on this, and who have kept it secret until now and we've all published together at the same time."
New Zealand's Inland Revenue said it had compliance systems in place to flush out those who used offshore trusts to hide their wealth and avoid tax.
The tax department said it regularly exchanged information with its tax treaty partners, including responses about foreign trusts set up locally.
It said it was trying to get more details of any New Zealanders who might have been involved with Mossack Fonseca.