Banda returned to Malawi at the weekend after four years of self-imposed exile, saying she had done nothing wrong and had no fear of being arrested.
But Malawi’s Anti-Corruption Bureau (ACB) dismissed claims that she had been cleared of all allegations over the “Cashgate” scandal, in which officials siphoned off millions of dollars of public money.
“This is not true,” ACB director general Reyneck Matemba told Wednesday’s Nation newspaper.
“We never said we have cleared the former president,” he said, adding that they had evidence from three suspects convicted over the scandal.
“We are following up on those allegations. I don’t think that is clearance,” Matemba said.
Since her return, Banda, 68, has said that the allegations against her were politically motivated.
Banda, who may launch a presidential bid in 2019 elections, was greeted by hundreds of supporters of her People’s Party (PP) when she arrived in Blantyre airport on Saturday.
Information Minister Nicholas Dausi said President Peter Mutharika was not involved in any decision whether to investigation into Banda.
“The ACB has investigation and prosecution powers. It is not up to the president to ask them to do that,” he said.
Malawi, one of the world’s poorest and aid-dependent countries, will hold presidential, parliamentary and council elections in May 2019.