Leading Irish citizens, now living in America, likely had their phones hacked by British tabloids according to a report in the Sunday Independent newspaper.
They are part of a group of well-known Irish figures from politicians to entertainment and business leaders who have been liaising with British investigators from the London Metropolitan Police at Scotland Yard who are leading the phone hacking scandal inquiry.
Top libel lawyer Paul Tweed says he is working on information that could blow the hacking case wide open in Ireland and in the US.
"My clients firmly believe that British newspapers here published information which could only have been obtained by hacking their voicemails. It is the only way this information could have found its way into the papers.
"In recent weeks, we have been liaising with the Met unit in relation to a number of high-profile Irish people based in Ireland and the United States.
"We are currently carrying out extensive investigations both in Ireland and in the United States and we have made significant progress and information on the extent of hacking in Ireland, which will come to light shortly.
"However, while the Met unit can provide confirmation in relation to the names of victims of phone hacking by the News of the World private investigator Glenn Mulcaire, they cannot provide confirmation in relation to interference with Irish-based landlines and mobiles.
"As a result, and where deemed appropriate, we will be calling on the gardai to actively investigate these complaints in due course."
The Leveson Inquiry in Britain is conducting a major investigation into the phone hacking scandal.