The family of Syria's President Bashar Al Assad are behind $40 million (Dh146.9m) of luxury property purchases in Russia.
An investigation by anti-corruption group Global Witness revealed the purchase of property in two Moscow skyscrapers.
The revelations come as the family seek new ways to move Syrian regime money beyond the reach of western sanctions.
The properties were bought in the upmarket Moscow City district by member's of Mr Al Assad's inner circle, including the Makhlouf family and Mr Al Assad's cousins.
The Makhlouf family, headed by Mr Al Assad's uncle Mohammed Makhlouf, are considered to be Syria’s richest and second most important family.
Before 2011, they controlled 60 per cent of the Syrian economy, and now almost all the family been sanctioned by the European Union and United States for their various roles in Mr Al Assad’s campaign of violence against his own people.
Global Witness said: "Our exposé of the Makhloufs’ properties is rare supporting evidence that lends substance to rumours of regime money being funnelled out of Syria throughout the war.
"Information about the regime’s assets and finances is notoriously scarce due to the terror fostered by Al Assad’s apparatus at home and abroad.
"Our investigation further shows that the loans secured against some of the properties could be for the purposes of laundering money from Syria into Moscow.
"This opens the possibility that the money could then be moved into other jurisdictions, such as the EU, where members of the family are sanctioned."
Many of the properties, worth $22.3m, were purchased by Hafez Makhlouf, one of Mr Al Assad's first cousins who has been sanctioned over allegations that he oversaw the torture and murder of anti-regime protesters.
The report said that loan deals against 11 of the properties were with offshore Lebanese companies.
Five other Makhlouf family members, including the wife of Syria's richest man, Rami Makhlouf, also purchased property there between December 2013 and June 2019.
Sberbank, Russia's largest bank, is alleged to have provided services for one of the properties. It has not commented.
The bank is not bound by EU or US sanctions law but it does have branches in major European and US financial centres, including London, Frankfurt and New York.
The report concluded: "There is little doubt that the money is tied to grave human rights abuses in Syria.
"All financial institutions must ensure that robust due diligence processes are in place to prevent tainted money, like that of the Makhloufs, entering the global financial system.
"Weaknesses in such processes allow abusive and kleptocratic rulers to enjoy the spoils of their illegal actions while the victims of such regimes, including the citizens of Syria, continue to suffer without recourse to justice."
Dmitry Peskov, the Kremlin spokesman, told The Times that Moscow did not know whether Mr Al Assad's relatives had bought property, adding: "In Russia we have an absolutely free market."