Former Malaysian PM Najib Razak has been arrested by anti-corruption authorities and is due to be charged on Wednesday.
Mr Najib, who has long been plagued by allegations of corruption, has been accused of pocketing $700m (£517m) from state development fund 1MDB.
Billions of dollars are unaccounted for from the fund, set up by Mr Najib.
He has been under investigation since his shock election loss in May. Mr Najib denies any wrongdoing.
In a pre-recorded video posted on Twitter, he appealed to the public not to believe the reports, saying that not all of the accusations were true. "I have not had a chance to defend myself," he said.
According to a statement by the 1MDB special task force, Mr Najib was arrested at 14:35 local time (06:35 GMT) at his house in relation to matters dealing with SRC, a subsidiary of 1MDB.
He will be charged at 08:30 on Wednesday at the Kuala Lumpur High Court.
Raids in recent weeks have been carried out across properties linked to Mr Najib.
Police say they recovered $273m in luxury goods and cash from a raid in June, calling the seizure of valuables the biggest in Malaysian history.
Jewellery accounted for the biggest portion of the seizure, with the most expensive item being a $1.6m diamond and gold necklace.
Michael Bristow, BBC News, Kuala Lumpur
Najib Razak's arrest came as no surprise: the new Malaysian government has been saying for some time that it has an almost perfect case against him. For several days, there were rumours that the detention was imminent.
Reporters gathered outside Mr Najib's home in Kuala Lumpur, determined to be there when it happened. Officials openly said it was expected. But there was still shock and disbelief when the news filtered through.
"There is a God!" shouted one jubilant man when he heard.
Not everyone, however, was pleased. As night fell, a small group of Mr Najib's supporters gathered outside the Malaysian Anti-Corruption Commission, where the former prime minister was being held. They chanted and sang, and then went home, leaving only journalists and the police behind.
On Wednesday, Mr Najib will appear in court for the start of what is likely to be a long and much-followed case.
Mr Najib has always denied the corruption charges and had been cleared by Malaysian authorities while in power, but he is being investigated by several other countries.
He has been banned from leaving Malaysia.
1MDB, set up by Mr Najib in 2009, was meant to turn Kuala Lumpur into a financial hub and boost the economy through strategic investments.
But it started to attract negative attention in early 2015 after it missed payments for some of the $11bn it owed to banks and bondholders.
Then the Wall Street Journal (WSJ) reported it had seen a paper trail that allegedly traced close to $700m from the fund to Mr Najib's personal bank accounts.
Mr Najib has consistently denied taking money from 1MDB or any public funds.