Paraguayan prosecutors on Saturday began questioning former president Santiago Pena over his alleged involvement in a banking crisis over which he was impeached a day earlier, a police source confirmed to AFP.
Pena, who is being investigated for breach of trust, influence peddling and embezzlement, entered the attorney general's office in the capital Asuncion through a side door shortly after 11:00 am (1400 GMT).
The prosecutor in charge of the probe, Christian Benitez, said that Pena could be formally charged as early as Saturday afternoon.
Senators voted unanimously on Friday to remove Paraguay's youngest-ever president from office, three days after the implosion of Ueno bank, one of the country's biggest lenders.
Pena, a conservative former finance minister, was placed under house arrest minutes after his impeachment.
Pena was succeeded by former vice president Pedro Alliana, who promised not to abandon the almost three million depositors, including pensioners, affected by Ueno's demise.
On the streets of Asuncion there was rejoicing at Pena's ouster.
"Justice has been done. Now we want him to give us back our money and go to jail," Jessica Aquino, 32, told AFP.
But the news that Alliana, who is from the same right-wing Colorado Party, would take over angered some demonstrators.
"He's from the same team, he knew about it (the trouble at Ueno)," Edson Vazquez complained to AFP.
The collapse of Ueno, which started out as a digital-first fintech company and grew into a major bank that handled the accounts of several state entities, rocked the usually stable South American nation.
US-backed Pena, who sold his stake in the group that controlled the bank last year, had offered his resignation.
But lawmakers pressed ahead with impeachment proceedings in order to strip him of the political immunity he would have enjoyed had he stepped down.
Thousands of people had taken to the streets furiously demanding their money back after the Central Bank took control of Ueno, citing fears for its solvency.
Advance payments to an unspecified number of depositors began on Thursday afternoon, a Central Bank official told AFP.
Pena's removal is a further blow for US President Donald Trump's network of allies in South America.
Trump's favorite for Brazilian president, Flavio Bolsonaro, was defeated by left-wing incumbent Lula Inacio Lula da Silva last month.
Alliana will serve out the remainder of Pena's term, which ends in 2028.
Writing on X Saturday, Juan Pablo Segura, US assistant secretary of state for Western hemisphere affairs, called Paraguay a "strategic partner, friend and ally of the United States" and said Washington looked forward to working with Alliana.
Lula, also reacting on X to events in Paraguay, said he looked forward to welcoming Alliana to Brazil soon.