Singaporean prosecutors and police are examining Goldman Sachs Group's relationship with the Malaysian state investment fund at the centre of global money laundering probes, people with knowledge of the matter said.
The Commercial Affairs Department, the police's economic crime unit, and prosecutors have interviewed current and former Goldman Sachs executives who worked on bond offerings from 1Malaysia Development Berhad, said the people, who asked not to be named because the queries are confidential.
Investigators are also looking into the firm's links with Malaysian financier Low Taek Jho, who the US has alleged controlled a plot to siphon billions of dollars from the bond proceeds, the people said.
Investigators' meetings with current and former Goldman Sachs employees are part of a criminal probe into fund flows related to 1MDB, the people said.
The bank itself is not the focus of the investigation, they said.
Neither Goldman Sachs nor its current or former employees have been publicly accused of criminal offences or charged in relation to the fund, whose dealings have sparked probes in Singapore, Switzerland and the US.
The interviews, which took place last month, add to the scrutiny the New York-based bank faces over its role in raising almost US$6 billion (S$8 billion) for 1MDB in 2012 and 2013. The money was meant for development projects but US prosecutors allege that the bulk of it was diverted by high-level 1MDB officials and their associates.
Investigators in Singapore have asked for details about specific meetings involving Goldman Sachs officials concerning the bond deals, the people said.
They have also quizzed the current and former bank employees about the nature of the firm's relationship with Mr Low, and whether he was considered a client, according to the people.
"We are unable to comment because investigations are ongoing," a spokesman at the Singapore Attorney-General's Chambers said. A Goldman Sachs spokesman declined to comment.
But Goldman Sachs's ties with 1MDB have already ensnared one former senior executive.
Mr Tim Leissner, the former chairman of South-east Asia who was the lead banker to the fund, has been barred from the financial industries in Singapore and the US. He left Goldman Sachs in February last year.
In the US, investigators have asked about Mr Leissner's interactions with Mr Roger Ng, a former Goldman colleague who worked on the 1MDB funding, according to a source, Bloomberg reported in April.
Mr Ng, a Malaysian, was head of Goldman's South-east Asian sales and trading business at the time of his resignation in April 2014. At the time, Goldman declined to provide a reason for his departure.
The 1MDB bonds were arranged and underwritten by Goldman Sachs International, the bank's London-based unit.
Both 1MDB and Malaysian Prime Minister Najib Razak, who formerly chaired its advisory board, have consistently denied any wrongdoing.
Representatives for 1MDB did not immediately respond to requests for comment.
Three calls to Mr Low's Hong Kong-based Jynwel Capital were not answered. Mr Low said through a representative in July that no wrongdoing has been proven in any jurisdiction on the alleged misappropriation of 1MDB funds.
While Abu Dhabi government-owned fund International Petroleum Investment Cofor has verified the guarantees it made on the 1MDB bonds, it denied ownership of a company known as Aabar BVI, to which 1MDB said it sent US$3.5 billion.