Denis O’Brien, Ireland’s largest media owner, is being investigated by the country’s Criminal Assets Bureau (CAB), the agency that identifies money gained through serious crime, according to The Guardian, which quoted a report in The Irish Times. Mr O’Brien lives in Malta for tax reasons.

The Irish Times, citing “a source with knowledge of the matter”, reported on Friday that the CAB will seek to interview O’Brien about the findings of the Moriarty tribunal.

“In its report, published in March 2011, that tribunal concluded that a mobile phone licence granted to a consortium led by O’Brien had been secured on its behalf by the then communications minister, Michael Lowry, following payments made to him by O’Brien. Both O’Brien and Lowry have strenuously denied the tribunal’s findings, saying they are wrong, and have challenged their authenticity,” The Guardian wrote.

According to the Irish Times’s front page story, the CAB has interviewed “a number of relevant witnesses” (but not including Lowry).

“The agency has gathered information in the Isle of Man and Spain, where transactions mentioned in the tribunal’s report took place.

CAB’s remit involves investigating the suspected proceeds of criminal conduct. If such assets are identified, the agency can seize them.

Tribunal reports and evidence gathered by tribunals cannot be used as evidence in court so CAB, in investigating matters covered by the Moriarty tribunal, has to gather its own evidence.”

Ireland’s Sunday Business Post also carried a front page article by its political editor, Pat Leahy, in which he reported that the CAB was studying documents about the matter that had not been seen by the tribunal.

Mr O’Brien is regarded as Ireland’s richest man. His wealth stemmed from his obtaining of the Esat Digifone mobile phone licence, which he subsequently sold off.

He is the largest shareholder in Independent News & Media (INM), the company that owns the Irish Independent, the Irish Daily Star, the Sunday World and Dublin’s Evening Herald plus 14 regional titles and, north of the border, the Belfast Telegraph.

O’Brien’s Communicorp group owns Ireland’s two major national commercial radio stations, Newstalk and Today FM, plus three regional stations.

He also has widespread non-media assets in Ireland, including in water, gas, hotels and football. His global interests include mobile phones in the Caribbean and aircraft leasing.