Harare — THE Reserve Bank of Zimbabwe said it has broadened forensic audits in the mining sector as it seeks to unearth cases of financial prejudices by mining firms.

It said a US-based audit firm, Alex Stewart International LLC has been contracted to undertake the audits.

Reserve Bank Governor Dr Gideon Gono said on Wednesday the audit firm has so far unearthed "very glaring discrepancies and financial prejudices to the country by some mining houses" and action would be taken.

The first report by Alex Stewart has uncovered tax evasions by Zimbabwe Platinum Holdings, the country's biggest mining firm and the defunct, Hartely Mineral Zimbabwe.

It alleges that Zimplats siphoned about US$113,4 million in unpaid taxes.

With penalties and interests for late payment, the amount could reach to more than US$300 million.

The magnitude of tax loss by Hartely Mining Zimbabwe could not be verified.

Zimplats has denied the allegations and is assisting the central bank with the investigations.

Dr Gono also revealed that while the audits were being broadened to cover all major mining houses, tighter measures would also be put in place to minimise mineral losses.

"We once again wish to remind stakeholders in the mining sector that forensic audits by international auditors highly qualified in this area in now fully underway," said Dr Gono.

"The focused audits are being broadened to cover all major mining houses, as well as introducing tighter oversight mechanisms at the country's exit points, currently highly porous borders."

Zimbabwe has realised little value from mineral exports due to smuggling.

Estimates by the central bank show that the country is loosing US$50 million every month through smuggling of minerals and under invoicing.

Between January and June 2008, mineral exports declined 14 percent to US$406,5 million from US$473,1 million realised in the same period last year.