Deutsche Bank’s headquarters in Frankfurt was searched by Germany’s federal police office, criminal prosecutors and the country’s financial watchdog BaFin, reported Financial Times (FT).

The raid followed a search warrant issued by Frankfurt’s district court based on the suspicion that some of the lender’s unnamed employees may have violated anti-money laundering laws.

The prosecutors did not reveal further details of the case.

Deutsche Bank, which confirmed the raid, said in a statement: “This is an investigative measure by the Frankfurt public prosecutor’s office in connection with suspicious activity reports filed by the bank. Deutsche Bank is fully cooperating with the authorities.”

A source privy to the raid told FT that the raid was linked to a payment by Rifaat al-Assad, an uncle of the Syrian president.

Last year, Assad was sentenced to four years in jail by a French court over money laundering.

While Assad is said to be not a direct client of the German lender, the bank had cleared at least one payment on behalf of a bank where he had an account, according to the report.

Deutsche Bank first identified the payment when it screened its data for Assad-linked transactions after his sentencing in France. The bank subsequently reported it to BaFin.

The German lender provides correspondent banking services to other lenders through its corporate bank. It acts as a middleman in such transactions and clears transnational money flows between the lenders.

Other sources told the publication that the raid was linked to potentially suspicious money that Deutsche Bank cleared as a correspondent bank. They didn’t confirm the identity of the individual involved.

The police search was prompted by the criminal prosecutor’s suspicion that the bank may have violated its legal obligations by not reporting the transaction earlier, they said.

In December last year, BaFin imposed an administrative fine of $9.8m on Deutsche for controls lapses associated with the Euribor interest rate.