Australia’s corporate watchdog has launched a major investigation into allegations into the conduct of senior executives and directors at CIMIC Group (formerly Leighton Holdings) amid allegations that they breached their duties as directors and failed to expose the existence of a multi-million-dollar bribery scandal, media reports have suggested.

And a senior leader who was responsible for the company’s compliance and integrity unit has resigned.

Fairfax Media has reported that the Australian Securities and Investments Commission is investigating whether or not directors and officers of CIMIC (then Leighton) breached their duties as directors by failing to take reasonable steps to deal with allegations of bribery made in respect of the Pakri Barwadih coal mining contract formerly held be Leighton subsidiary Thiess in India.

According to the report, ASIC is looking into whether or not directors breached their duties by failing to take reasonable steps over the period spanning August 2, 2012 to April 7 2016 to deal with allegations that Thiess’s Indian partner property developer Syam Reddy was paying or promising to pay as much as $16 million in bribes to Indian politicians and officials in order to ensure that Thiess was able to secure a $6.8 billion coal mining contract in 2008.

Those allegations are contained in report delivered to Leighton by external auditors in 201, which reportedly describes how Thiess executives failed to act upon warnings with regard to the contract.

The watchdog is reportedly also investigating allegations that CIMIC breached its obligations to investors by failing to inform the market about Thiess bribery allegations.

The investigations reportedly began weeks ago but have remained secret until now.

The revelations come as CIMIC Group director Dr Kirsten Ferguson resigned on November 10 from her role as an independent director of the company.

Previous Fairfax reports had indicated that Ferguson – who was also chair of CIMICS Ethics, Compliance and Sustainability Committee – was under pressure over her handling of a whistle blower who reportedly alerted her to the corruption scandal only to have his concerns ignored and for him to be sacked in 2014.

Ferguson faces questions about what action, if any, she took to protect the whistle blower and to ensure that the alleged corruption was properly and appropriately investigated.

In its announcement, CIMIC says Dr Ferguson cited ‘upcoming commitments’ as a reason for her departure and thanked her for commitment, integrity and diligence.

The investigations come as the Australian Federal Police has an ongoing investigation into CIMIC for allegedly paying bribes over a separate scandal in Iraq.