(Bloomberg) -- Citigroup Inc.’s Singapore subsidiary and CIMB Group Holdings Bhd are among banks affected by a major money laundering case in the city-state involving about S$1 billion ($736 million) of assets.

The two lenders were used in 2020 and 2021 by some of the foreign nationals who were arrested in raids this week across the country, according to charge documents seen by Bloomberg News. 

Turkish national Vang Shuiming was charged for allegedly submitting a fake document to Citibank Singapore Ltd., while Cambodian national Su Baolin was charged for falsely claiming he was an executive director of a firm in a supporting document to the US bank. Meanwhile, two Chinese nationals, Zhang Ruijin and Lin Baoying, were charged for seeking to cheat CIMB Bank Bhd. about their ownership and sale of a property in Macau. 

A Singapore-based spokesperson for Citigroup declined to comment in response to questions from Bloomberg News.

Malaysia-based CIMB said in a statement that it “does not comment on any individuals, on-going investigations, or court proceedings” and “is fully committed to strong corporate governance and strict compliance with banking standards, laws and regulations.”

The accused are in remand and couldn’t be reached for comment.

Read More: Singapore Charges 10 in $736 Million Money Laundering Ring

The Monetary Authority of Singapore said on Wednesday that suspicious fund flows, dubious documentation of the source of wealth as well as other inconsistencies prompted unnamed banks to file suspicious transaction reports to authorities. The information from such reports had alerted the police to suspicious activities that have been attempted through the country’s financial system.  

The regulator added it will take firm action against financial institutions if there are breaches of anti-money laundering rules. It is also conducting inspections focusing on financial firms active in wealth management, to ensure robust controls are in place.  

--With assistance from Alfred Cang.

(Updates with CIMB statement in fourth paragraph)

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