The potential benefit to Singapore from the turmoil in Hong Kong: $4 billion.

That is the upper end of an estimate from Goldman Sachs Group Inc. of the money that investors have moved to Singapore amid escalating political protests in the former British colony.

The New York-based bank estimated that there has been a maximum outflow of Hong Kong dollar deposits totaling $3 billion to $4 billion to Singapore, an alternative financial center for the region, as of August.

Local-currency deposits declined in August by 1.6 percent from the previous month, the biggest drop in more than a year, to about 6.84 trillion Hong Kong dollars ($873 billion), the Hong Kong Monetary Authority said earlier this week. Its chief attributed that slump to a dearth of initial public offerings and said there had been a slight increase in the first three weeks of September. That was before a further escalation in violence in the city.

"We found modest net outflow from HKD deposits in Hong Kong and modest net inflow of FX deposits in Singapore," analysts Gurpreet Singh Sahi and Yingqiang Guo wrote in a note to investors. "We believe the debate on Hong Kong outflow/liquidity will remain active and the data points for September (and beyond) critical in shaping the same."

Hong Kong reportedly is set to impose curfews, ban masks and invoke other powers under a controversial colonial-era emergency law as it struggles to control the escalating unrest.