Details from a trove of 200,000 documents obtained from the former Mauritius office of law firm Conyers have been published by an investigative journalism website.

Conyers said yesterday that the confidential papers had been “illegally obtained” and that authorities in Mauritius had been notified.

The International Consortium of Investigative Journalists published data associated with the documents yesterday, claiming it was doing so “in the public interest” and naming the investigation the “Mauritius Leaks”.

Details of more than 200 companies assisted by Conyers’ Mauritius office, including appliance maker Whirlpool and oil giant Total, are revealed. Private-equity firm 8 Miles LLP, founded by Bob Geldof, the former Boomtown Rats singer and Live Aid organiser, also gets a mention.

Conyers Dill and Pearman started up in Bermuda 90 years ago and this year rebranded as Conyers. In 2009, it set up an operation in Mauritius, an island in the Indian Ocean, about 1,200 miles off the southeastern coast of Africa.

“Mauritius Leaks and ICIJ’s previous investigations have shown how the offshore economy facilitates money laundering, tax evasion, fraud and other types of crime,” the ICIJ stated in a report on its website yesterday.

“Transparency advocates argue that even when offshore companies’ activities are legal, their secrecy can undermine democracy.”

In a video on the ICIJ website, Will Fitzgibbon, the organisation’s African partnership coordinator, described how the investigation started when an anonymous source left an envelope containing a USB key that held hundreds of thousands of confidential documents.

Conyers said yesterday that it ceased operations in Mauritius in April 2018. Former members of the firm now operate as Venture Law Ltd, which engaged a third-party data security company to investigate and determine the scope of the issue.

“Our clients are our top priority and we are sorry that their confidential business information has been stolen and made public in this way,” Christian Luthi, chairman of Conyers, said. “We are investigating the sources and extent of the data theft as a matter of urgency.

“Our investigations to date show that only a limited number of files from our former Mauritius office were taken. Conyers is contacting clients that we know to have been affected.”

Mr Luthi added: “Conyers strictly adheres to the laws of all the jurisdictions in which we operate and upon which we are asked to advise. The firm does not and will not comment on confidential matters relating to our clients. I invite clients with questions or concerns to contact me directly on chairman@conyers.com.”

He added that Conyers had “comprehensively investigated” its IT infrastructure and was confident that the firm’s systems had not been compromised.

Mr Luthi added: “We take information security protocols very seriously. Conyers’ technology practices regarding data protection and information security meet or exceed current industry standards. Our data security policies and procedures are certified by ISO27001.”

The ICIJ also led the publication of the “Panama Papers”, after obtaining 11.5 million documents from the offices of Panama law firm Mossack Fonseca in 2015.

And two years ago, the ICIJ worked on the “Paradise Papers”, a set of 13.4 million documents that originated from the offices of Appleby, another firm that was founded in Bermuda.

The details published yesterday do not appear to accuse anyone or any company of acting illegally. Rather they use excerpts and details from the documents to illustrate how companies set up entities in Mauritius with the expressed intention of reducing their tax liabilities in regions including Africa, Asia, the Middle East and the Americas.

The reports suggest that Mauritius projects itself as a “gateway” for corporations in the developing world, with its main selling points being low tax rates and tax treaties with 46 mostly poorer countries.

Mr Fitzgibbon wrote: “The investigation reveals how multinational corporations took advantage of some of the world’s poorest countries, especially in Africa, extracting profits and avoiding taxes through the use of shell companies in Mauritius.”

One of the batch of ICIJ articles highlights how Mr Geldof’s UK-based private-equity firm wanted to invest in businesses on the African continent through Mauritius, more than 2,000 miles away. It quotes an e-mail from a London-based lawyer suggesting that the motivation was “tax reasons”.

Mr Geldof, well known for organising the Live Aid concert of rock stars in London and Philadelphia in 1985 that raised $140 million for famine relief in Ethiopia — efforts that earned him an honorary knighthood — has long championed investing in African small and medium-sized businesses.

His firm 8 Miles invests in companies in Uganda, Egypt and Ethiopia, according to regulatory filings.

A spokesman for 8 Miles said its investors had requested that their funds be consolidated in a “safe African financial jurisdiction for onward investment” and that Mauritius fitted the bill.

On its website, Conyers says its client base includes Fortune 500 and FTSE 100 companies, international finance houses and asset managers.

Besides Bermuda, the firm has operations in the British Virgin Islands, the Cayman Islands, Hong Kong, Singapore and London.