Former Malaysian Prime Minister Najib Razak, shown here in May, has been arrested over questions about corruption involving billions of dollars in a government fund.
Dr Mahathir also told Reuters in an interview last month that embezzlement and bribery with government money were among the charges that the Pakatan Harapan government was looking to bring against Najib, adding they had "an nearly flawless case" against him.
Najib has been investigated over suspicions that he may have siphoned off monies linked to a state investment fund called 1MDB.
Anti-graft agents picked up Najib from his home after serving him with a remand order, two sources close to the family said.
A lawyer representing Najib could not immediately be reached.
Mr Najib, who has always been plagued by allegations of corruption, has been accused of pocketing $700m (£517m) from state development fund 1MDB.
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Vettel would recover through a mixture of strong pace, tyre management and strategy, to finish third come the checkered flag. However, his race got much worse as his Mercedes lost power, and he had to retire with a technical issue.
The United States' Department of Justice filed lawsuits to seize about US$1.7 billion in assets that it said had been bought with money misappropriated from 1MDB, including real estate in NY and southern California, artwork, and a luxury yacht.
Shortly after his ouster, a vast trove of valuables was seized in raids on properties linked Najib and his family, including cash, jewellery and luxury handbags, worth up to $273 million.
That Wolf of Wall Street-related corruption case you may have read a thing or three about has now resulted in the arrest of former Malaysian prime minister Najib Razak. Mr Najib denies wrongdoing. Najib is expected to face more charges over the 1MDB scandal and his prosecution could take years, because the former PM has indicated he will mount a rigorous defence against the accusations thrown at him. Red Granite in March agreed to pay the USA government $60 million to settle claims that it benefited from the 1MDB scandal. Red Granite was unavailable for comment.
They say a figure called "Malaysian Official 1" was given large sums of money from 1MDB.
Najib set up the 1Malaysia Development Bhd government investment fund in 2009, and as NPR's Elise Hu has reported, it rapidly amassed billions of dollars in debt.