Construction companies paid out €151.4 million in previously-unpaid taxes and related penalties and interest last year after the Revenue Commissioners conducted almost 44,000 checks and audits in the sector.

Figures released by Revenue yesterday also showed that the tax authority's special investigations in areas such as offshore assets, bogus non-resident accounts and life assurance products brought in €132.2 million in 2007.

This brought the total yielded from these ongoing activities to €2.4 billion over 32,630 cases.

Ansbacher cases, including a €4 million settlement with the estate of the late Des Traynor, accounted for the largest portion of the 2007 yield from special investigations.

Frank Daly, chairman of the Revenue Commissioners, said the 2007 figures represented a successful year for the tax authority, and sought to remind taxpayers of Revenue's role in society.

"Certainly, our work delivers the resources for schools, roads, hospitals and the myriad of other services that add to everybody's quality of life - but it also plays a critical role in encouraging economic development and protecting society," Mr Daly said.

Revenue carried out 3,807 full audits of construction companies in 2007 as part of a plan to target companies working in the area.

The audits, which involved an extensive examination of a firm's books, yielded €129.6 million, or an average of €34,000 per construction company.

Revenue also completed 40,161 assurance checks on building firms last year, delivering a further €21.8 million.

These checks are designed to allow Revenue to satisfy itself that a taxpayer is tax-compliant without a full audit.

The construction sector as a whole accounted for 26 per cent of audits carried out by Revenue last year, and provided 19 per cent of the total yield from audits.

Revenue plans to dedicate "at least 12 per cent" of its compliance resources to the sector this year.

The tax authority conducted a total of 14,550 audits in 2007, compared to 13,626 in the previous year. It conducted a further 237,000 assurance checks last year, up from 176,064 in 2006.

Revenue's latest figures also show that the authority obtained 14 convictions in relation to "serious evasion" last year, with an additional 60 investigations ongoing and 41 cases before the courts or being considered by the Director of Public Prosecutions.

Under its customs wing the commissioners made 2,363 seizures of drugs worth €135 million in 2007, and seized cigarettes and tobacco worth €24.4 million.

Joan Burton, Labour's finance spokeswoman, said Revenue was entitled to "considerable public gratitude" for its work, but added that the figures showed that tax evasion remained "a major phenomenon".

She said the construction sector should continue to be an area of focus for Revenue this year.