Billions of dollars were allegedly stolen from the fund in a sophisticated fraud, and used to buy everything from artworks to high-end real estate.

Najib and his reviled, luxury-loving wife Rosmah Mansor have had a swift fall from grace. They have been barred from leaving the country, and police have seized handbags, jewels and cash during raids on properties linked to the couple.

Public disgust at the corruption allegations swirling around them at a time middle-class Malaysians were suffering due to rising living costs and stagnant salaries was seen as a major factor in Najib’s defeat.

The ousted leader arrived at the Malaysian Anti-Corruption Commission (MACC) headquarters in the administrative capital of Putrajaya, walking through a scrum of about 100 journalists.

Najib was summoned by the MACC to give a statement over claims millions of dollars from SRC International, an energy company that was originally a subsidiary of 1MDB, ended up in his personal bank accounts.

It is just one small part in the graft scandal, which is being investigated in several countries. As speculation swirls about an imminent detention, the new MACC chief, Shukri Abdull, said Najib would not be charged on Tuesday.

The toppled regime went to great lengths to suppress scrutiny of the problems surrounding 1MDB, closing down domestic probes, sacking critics from government, jailing those who spoke out and muzzling the media.

Shukri, a long-time senior figure in the anti-graft agency who retired but has been brought back by Mahathir, shed tears at a press conference as he told how he came under “tremendous pressure” during an earlier probe into 1MDB.

Shukri said his agency had been poised to launch a case in 2015 against Najib but had been stopped in its tracks by the sacking of the attorney-general. Recounting events back then, Shukri gave the most revealing account so far of the cover-up.

“We had our own intelligence sources, that I would be arrested and locked up, because I was accused as being part of a conspiracy to bring down the government,” Shukri said, shedding tears briefly as he made his opening remarks.

“I was sent a bullet to my house. I never told my wife or my family. I never even made a police report.”

He went on to describe how he received police protection during a visit to the United States after suspecting that he was being followed by Malaysian security officials.

“We wanted to bring back money that was stolen back to our country. Instead we were accused of bringing down the country, we were accused of being traitors,” Shukri said.

As pressure mounted, Shukri decided to retire in 2016.

According to an investigation by The Wall Street Journal, 42 million ringgit (US$10.6 million) originating from SRC was transferred to Najib’s personal bank accounts.

Hundreds of millions of dollars from 1MDB allegedly ended up there.

Najib and 1MDB have denied any wrongdoing. A domestic investigation launched during his premiership concluded that the money in his accounts was a donation from the Saudi royal family.

Mahathir has vowed to fully investigate the financial scandal and on Monday the new government set up a task force headed by high-ranking current and former officials to probe the controversy.

Following the fall of the corruption-riddled regime, which had led Malaysia since independence from Britain in 1957, figures linked to the 1MDB scandal have been making appearances.

Mahathir met at the weekend with Xavier Justo, a former executive with PetroSaudi, a company that was allegedly involved in corrupt deals with 1MDB.

The Swiss national is believed to have leaked documents related to the scandal to the media. He was jailed in Thailand for attempting to blackmail his former employer but was released in 2016.

Additional reporting by Reuters