Authorities found that one or more of the accused in the case involving more than S$2.8 billion (US$2 billion) of assets, may have been linked to single family offices that were awarded tax incentives, minister of state Alvin Tan said in parliament on Tuesday.

Singapore has seen an influx of family offices — set up by ultra rich to manage their affairs and investments — on the back of its growing appeal as a financial hub. The number of single family offices there rose to 1,100 by the end of last year, compared with just 400 in end 2020.

The laundering scandal, ballooning into one of the largest in the country, shines a light on potential loopholes and has ensnared major banks and property agents.

The minister said that the Monetary Authority of Singapore has not detected any “adverse information of note” related to the individuals and entities when they applied for the incentives. “Nonetheless, MAS is reviewing our internal incentive administration processes, and will tighten them where necessary,” he said.

It’s unclear which of the 10 alleged criminals, all of Chinese origin and arrested in raids across the island in mid-August, were linked to which family offices.

The MAS said in July it will boost surveillance and safeguards against laundering risks in the family office space and tighten requirements for those seeking so-called 13O and 13U tax exemptions. A recent public consultation on the new rules just concluded.

Minister Tan said the MAS will “study whether further measures beyond those that have been proposed in the consultation are necessary.”