Malawi's former President Bakili Muluzi has been released on bail after being charged with corruption and fraud.
Mr Muluzi has fallen out with his successor as president
After his arrest on Thursday morning, he was questioned by anti-corruption agents about financial transactions during his time in power.
A spokesman for Mr Muluzi's United Democratic Front (UDF) party said the move did not come as a surprise, and called it "political persecution".
Mr Muluzi fell out with his successor Bingu wa Mutharika after polls in 2004.
Anti-Corruption Bureau (ACB) Director Gustave Kaliwo told a press conference that the former president was being charged with 42 counts of corruption, fraud and theft.
He said that some of the allegations related to donor money that had ended up in Mr Muluzi's personal account during his time in office.
"These are allegations we are making; Dr Muluzi should be perceived innocent until proven otherwise," he said.
Mr Muluzi's lawyer told journalists that the former president had remained silent during his one-and-a-half hour interrogation.
"We would rather the former president make full explanation to the nation in court and we are very confident he will be found very, very innocent," Fahad Assani said.
The BBC's Raphael Tenthani in Blantyre says Mr Muluzi looked unshaken by his experience.
Bingu wa Mutharika felt a backlash from his anti-graft drive
Donning a black suit and flanked by political allies, he came out the ACB's offices smiling broadly to his chanting supporters, our correspondent says.
Earlier, there was commotion in parliament when MPs heard about Mr Muluzi's arrest.
The speaker, unable to control the situation, suspended the session in which MPs are already at loggerheads over the budget that should have been agreed last month.
The UDF's publicity secretary Sam Mpasu said the development was "a continuation of political persecution".
Mr Muluzi stepped down as president after serving two terms in office in 2004.
He hand-picked Mr Mutharika to run for president on the UDF ticket.
But eight months after his victory, the new president resigned from the UDF over what he says was hostility to his anti-corruption campaign.
In April, Vice-President Cassim Chilumpha, who is close to Mr Muluzi, was arrested and charged with treason.
He is on bail under strict conditions and may not leave his house without permission from the president.