Australian police arrested a former executive of construction company Leighton Holdings on Monday in connection with an international bribery investigation involving Monaco-based consultancy Unaoil.

David Savage, a former chief operating officer of Leighton, which has since been rebranded Cimic, was charged with knowingly providing misleading information to authorities contrary to Australian law.

The main targets of the bribery scheme were Iraqi oil ministry officials and government officials within the South Oil Company of Iraq, police said in a statement.

Investigators identified $77.5m in suspicious payments made via third-party contractors and allege Leighton Offshore PTY Ltd funnelled bribes through Unaoil and another Middle Eastern subcontractor to guarantee contracts.

Leighton won contracts with a combined value of $1.46bn in 2010 and 2011, which required approvals from officials at Iraq’s oil ministry and South Oil Company of Iraq, the police said.

The arrest of Mr Savage is part of a long-running corruption investigation by UK, US and Australian police into allegations that agents of Unaoil paid multimillion-dollar bribes to secure oil contracts for multinational companies in war-ravaged Iraq and several other nations.

The investigation has already achieved significant success with two senior Unaoil managers convicted on bribery charges last year by a UK court for paying bribes to clinch more than A$1bn in contracts.

And in 2019 two brothers from the Ahsani family, who ran Unaoil, Saman and Cyrus, pleaded guilty in the US to being part of 17-year scheme to pay millions of dollars in bribes to officials in nine countries.

Australian police began investigating the bribery claims in November 2011 when Leighton Holdings reported to them allegations of improper payments made by Singapore registered operating entity Leighton Offshore PTY. The investigation revealed two contracts for the development and installation of onshore and offshore gas pipelines, which aimed to increase the capacity of Iraq’s oil exports.

Mr Savage was arrested by police after his return to Australia from France and two weeks spent in hotel quarantine owing to Covid-19. The 60-year-old former executive is expected to appear in a Sydney court via video link on Monday.

Mr Savage is the second former Leighton executive to face charges over the alleged bribery scandal. In November police arrested Russell Waugh, a former managing director of Leighton Offshore, on foreign bribery charges.

Nine newspapers, which first reported Unaoil’s involvement in bribery via a vast data leak, said the charges against Mr Waugh were made possible by the decision by the Ahsani brothers to co-operate with Australian authorities.

Cimic said it had no comment, while Mr Savage could not be contacted for comment.