Najib smiled and waved to reporters before entering the Malaysian Anti-Corruption Commission building for the second time since his shocking ouster in May 9 national elections that were marked by public anger over the scandal. He has denied any wrongdoing but Malaysia's new anti-graft chief has said Najib could face criminal charges "very soon."
He told reporters when he left the building that the agency has finished questioning him.
On Tuesday, Najib was grilled for more than four hours over why 42 million ringgit ($10.6 million) was transferred into his bank account from SRC International, a former unit of the 1MDB fund, using multiple intermediary companies.
That transfer was in addition to some $700 million of 1MDB funds U.S. investigators say landed in Najib's bank account. Najib set up 1MDB when he took office in 2009 but it accumulated large debts and is being investigated in several countries. The U.S. Justice Department says Najib's associates stole and laundered $4.5 billion from the fund.
Xavier Andre Justo, a whistleblower in the 1MDB case who met with new Prime Minister Mahathir Mohamad earlier this week, also appeared at the anti-graft agency on Thursday just before Najib arrived. He didn't speak to reporters.
An anti-graft official, who declined to be identified because the matter is sensitive, said Justo is assisting a taskforce investigating 1MDB but couldn't give further details.
The 1MDB taskforce said in a statement Thursday that it met officials from the U.S. Justice Department and the FBI who complained they previously couldn't get Malaysia's cooperation to investigate the case. The taskforce said they will cooperate in the U.S. probe and will seek to retrieve laundered 1MDB funds.
Najib and his wife were barred from leaving the country after the new government reopened an investigation into the scandal. Police have raided Najib's home and other properties linked to him, seizing hundreds of expensive designer handbags and luggage stuffed with cash, jewelry and other valuables.
New Finance Minister Lim Guan Eng said this week that Najib's government had conducted "an exercise of deception" over 1MDB and misrepresented the country's financial situation to parliament.
In a statement on social media late Wednesday, Najib disputed Lim's assertion that government debt had ballooned to more than 1 trillion ringgit ($251 million). He accused the government of wanting to "slander and put all the blame on me to give a perception of a dire financial position to justify why you cannot deliver on your manifesto promises and to massively cut the civil service."
In response, Lim said Thursday that Najib's government failed to take into account some 400 billion ringgit ($100 million) in government guarantees and lease payments for projects that will take national debt to 1.09 trillion ringgit.
Lim said the finance ministry had bailed out 1MDB by paying nearly 7 billion ringgit ($1.76 billion) to service its debts since April 2017, contrary to 1MDB's claim that the money was from a rationalization exercise. He said the government will honor millions of dollars due in 1MDB debt this year.
Malaysia has to "bite the bullet" in the short term to regularize its financial situation but economic fundamentals remain strong and the banking sector is stable, he added.
Mahathir, who had been prime minister for 22 years until 2003 and was spurred out of retirement by the 1MDB scandal, has vowed there will be "no deal" for Najib, saying he will "face the consequences" if found guilty of wrongdoing.
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