IT worker at law firm Mossack Fonseca arrested in Geneva

Arrest over the leak of "a large volume of confidential data", according to Swiss newspaper

An IT worker at Mossack Fonseca has been arrested in connection with the leak of "a large volume of confidential data" from the Panama-based law firm, according to a Swiss newspaper.

However, it is not yet clear whether the member of staff is accused of involvement in the security breach at the law firm in April in which 11.5 million confidential client documents were leaked to the media, or whether the arrest involves other unspecified alleged breaches.

According to Le Temps, the IT worker has been accused of theft of data, unauthorised access and a breach of trust following a complaint from the law firm. He has denied breaking any laws, but was arrested following a search of the company's offices and the seizure of computers by the Geneva prosecutor.

The prosecutor has refused to reveal further details about the arrested individual, but the law firm released the following statement: "We are confident that the authorities... will carry out the corresponding processes transparently and effectively in every case."

The security breach at the law firm in April indicated the large number of companies and individuals that were using its services, one of many that helps individuals and companies to set up corporate structures in tax havens, to keep their wealth offshore.

Among the individuals identified in the leak were close associates of Russian president Vladimir Putin, relatives of China's leader Xi Jinping and footballer Lionel Messi, who is currently on trial on charges of tax evasion in Spain. A total of 140 politicians and 29 billionaires were implicated as customers for Mossack Fonseca's services.

The scale of the breach indicated that the attacker, whether an insider or not, exfiltrated the documents over a matter of weeks or months.

The individual behind the leak - made to German newspaper Suddeutsche Zeitung, possibly indicating that the attacker was German, Austrian or Swiss-German - published his own manifesto in May giving his reasons for leaking the documents.