Take a look inside Unaoil, the Monaco oil services firm which funneled huge sums of cash between multinational companies and government officials.

The headquarters of the Monaco-based oil company Unaoil and the homes of its executives have been raided by police in the wake of revelations in recent days that it has systematically corrupted the global oil industry.

In a statement, the Monaco government said it was helping British authorities investigate the "vast corruption scandal" revealed in recent days by Fairfax Media and The Huffington Post. Fairfax Media publishes the Sydney Morning Herald, The Age, The Brisbane Times and Stuff.co.nz.

Police moved after the story broke the story late on Wednesday that Unaoil and its owners, the Ahsani family, used multi-million dollar commissions to bribe corrupt governments in oil rich states to win contracts for large western firms such as Rolls-Royce, Halliburton and Australia's Leighton Offshore.

FAIRFAX MEDIA Cyrus Ahsani (left) and wife Sany, and Saman Ahsani (second right).

The statement from the Monaco government said that several of the company's senior executives had been questioned over the past few days and their homes and headquarters searched following an urgent request from Britain's Serious Fraud Office.

READ MORE:

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* Unaoil bribery scandal: The oil, the powerful and the multinationals

* Codenames, subterfuge and global money trail

* Unaoil bribery scandal: The worldwide players

* Unaoil bribery scandal: Monaco bribe masters

* Unaoil bribery scandal: The Australian angle

"Monaco authorities conducted searches of the homes of the leaders of the company Unaoil and at its headquarters in the Principality," the statement said.

"The leaders of this company were also interviewed on 29 and 30 March 2016. These searches and interviews were conducted in the presence of British officers, in connection with a case of vast corruption with international ramifications that involves many foreign companies active in the petroleum sector.

"The items collected during the search will be now be used by the British authorities in their investigations."

It was revealed on Thursday that the British police had teamed up with the Australian Federal Police, the US Department of Justice and the FBI to investigate the vast cache of emails on which our stories have been based.

The Monaco government said it would not release further details at this stage in case it compromised the investigation.

A spokeswoman for Unaoil told Associated Press the company "has no comment at this time". The Serious Fraud Office also declined to comment.

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