Burundi's sacked central bank governor has been arrested on suspicion of money laundering and misappropriation of public assets.
The charges against Dieudonné Murengerantwari are "provisional" pending the outcome of investigations, the justice ministry said.
Mr Murengerantwari has not yet responded to the allegations.
On Sunday, Burundi's President Évariste Ndayishimiye fired him, just over a year after he took up the post.
Burundi's economy is in deep crisis with a shortage of foreign currency that has made it difficult to import goods.
It also faces a shortage of fuel, and rising prices.
About 65% of the population of 12 million live in poverty, according to the World Bank.
In a statement, the justice ministry accused Mr Murengerantwari of "undermining the proper functioning of the national economy, passive corruption, money laundering and misappropriation of public assets".
It did not give further details, but Attorney General Leonard Manirakiza said the ex-governor would remain in custody while investigations continued.
Mr Murengerantwari was appointed to the post - which is vital to achieving economic stability - for five years, but was dismissed in his second year in office.
He was previously the managing director of Burundi's state-linked development bank.
He has been replaced by a member of the bank's board, Édouard Normand Bigendako.
Mr Murengerantwari is the second central bank chief in Africa to run into legal trouble this year.
Nigeria's central bank governor Godwin Emefiele was suspended in June, and later charged with illegally owning a shotgun and cartridges. He denied the charges.