Authorities across the world are being spurred into action after a huge leak of confidential documents revealed how tax havens are used to hide wealth.
A leak of 11 million documents from Panamanian law firm Mossack Fonseca revealed how scores of the world's wealthy elite use it to set up tax shelters, including in New Zealand.
Since the first revelations late on Sunday a number of investigations have been launched by Austrian, Dutch and Australian authorities, among others.
The documents, feature 12 current or former heads of state, and at least 60 people linked to current or former world leaders.
The company says it has operated beyond reproach for 40 years and has never been charged with criminal wrongdoing.
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The files reveal a suspected billion-dollar money laundering ring involving close associates of Russia's President Vladimir Putin.
Iceland's Prime Minister, Sigmundur David Gunnlaugsson, is also shown to have had an undeclared interest linked to his wife's wealth.
By Monday morning, 16,000 people in Iceland had signed a petition demanding his resignation, but he has ruled out stepping down.
The leaked documents also show that Ian Cameron, the late father of UK Prime Minister David Cameron, was a Mossack Fonseca client.
Also mentioned are the brother-in-law of China's President Xi Jinping; Ukraine's President Petro Poroshenko; and Argentina's President Mauricio Macri.
The massive leak to German investigative newspaper Süddeutsche Zeitung, from an anonymous source, was then shared with the International Consortium of Investigative Journalists (ICIJ) which organised an investigation by news organisations around the world.
Since the files became public, Australia's tax office has said it is investigating 800 individuals named in the leaks. New Zealand's IRD 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.
Britain's tax authority HM Revenue and Customs (HMRC) says it has received "a great deal of information on offshore companies" as it investigates and is also asking the ICIJ to share all its data.
France's finance ministry is seeking the original documents in the leak for its own investigation, while Austria's financial markets regulator says it is investigating whether two banks breached rules on money laundering after being named in the leaks
In Pakistan, Hussain Nawaz Sharif, son of Prime Minister Nawaz Sharif and one of three siblings shown to own real estate through offshore entities, said "there is nothing wrong with it."
A spokesman for Azerbaijan's president Ilham Aliyev, whose children are named as owners of offshore companies, says such practice "is not banned by any law", adding that they "are grown up Azerbaijani citizens"
China appears to be censoring social media posts on the document leak, which has named several members of the country's elite
The documents reveal for the first time details of an operation run by a Russian bank and which involves close associates of President Putin. Kremlin spokesman Dmitry Peskov said it was clear the main target of the reports was Mr Putin, as well as Russia's political stability ahead of parliamentary elections.
Mr Peskov dismissed the investigation as insinuation and speculation, and suggested many of the team of journalists behind it were actually former US state department and CIA officials.
Another case highlights how Mossack Fonseca offered financial services designed to help business clients hide their wealth. One wealthy client was offered fake ownership records to hide money from the authorities.
Mossack Fonseca says offshore companies are available worldwide and are used for a variety of legitimate purposes.
"If we detect suspicious activity or misconduct, we are quick to report it to the authorities," it said. "Similarly, when authorities approach us with evidence of possible misconduct, we always co-operate fully with them."