David Drumm (left) and Sean Fitzpatrick: main targets of the investigation

A MAJOR file arising out of the investigation into irregularities at Anglo Irish Bank will be sent to the Director of Public Prosecutions (DPP) this week, the Sunday Tribune can reveal.

It is understood that the file represents a major piece of work including a lengthy summary document of around 200 pages. It is also understood that a further batch of some 39 documents are being completed to be presented to the DPP in the coming weeks. The investigation remains ongoing.

Gardaí are said to be confident that "the DPP will direct that charges are brought against some individuals" at the beleaguered bank. The main targets of the investigation are the former chairman Sean FitzPatrick and chief executive David Drumm. One source added: "The fraud squad detectives have had continuous meetings with the DPP's office about the progression of the investigation. The commissioner is being kept totally up to speed and readily briefed."

It was well-known there was huge frustration in government circles at the length of time it has taken to advance the investigation although there was an acc­eptance that investigators were swamp­ed with information and that "every 'i' had to be dotted and 't' crossed to ensure that nobody gets off on a technicality".

It is understood that Taoiseach Brian Cowen, justice minister Dermot Ahern and enterprise minister Batt O'Keefe have been regularly briefed on the investigation's progress.

Ahern will also bring a bill to cabinet this week which arises out of recommendations from the Garda commissioner on tightening up the laws on white-collar crime. It is understood the recommendations include allowing gardaí to break up detention periods for those arrested to help with inquiries. The idea is that instead of a person being held for 24 consecutive hours, it could be spread over a number of shorter detention periods which allow him or her to be questioned about new information that has emerged.

There is also likely to be increased powers to compel witnesses to give statements. The plan is to fast-track the legislation to allow it become law before the current Dáil dissolves which means it could be used in the ongoing investigation into Anglo Irish Bank.

Gardaí and the Director of Corporate Enforcement have been investigating events leading up to the nationalisation of Anglo in 2009, including whether loans were used to prop up the bank's shares.

The investigation ranks as one of the most complex of its kind in the history of the state as gardaí have examined over 115,000 emails and statements have been taken from 350 people.