Former first lady of Zambia, Esther Lungu, and her daughter Chiyeso Katete were arrested for possession of properties suspected of being proceeds of crime.
The two were detained on Thursday in the capital, Lusaka, along with another close family member identified as Charles Phiri, authorities said.
Lungu “failed to give a reasonable explanation” of how he acquired a $30,000 (£24,000) property in the capital, the state drug agency said.
Former president Edgar Lungu said the family would contest the charges in court.
The former leader has accused the government of victimizing him and members of his Patriotic Front (PF) party to block his return to politics before the 2026 elections.
He recently claimed to have been placed under house arrest because of his intense political activities, although the government denies.
Last September, his wife was arrested on corruption charges, involving cases of theft of motor vehicles and property titles, which she denied.
On Thursday, Lungu, 66, was arrested on suspicion of fraudulently purchasing a luxury property in Lusaka, the Drug Enforcement Commission (DEC) said in a statement.
It stated that Lungu owned “15 white two-storey apartments” situated in the State Lodge area of Chongwe town in Lusaka, “reasonably suspected to be proceeds of crime”.
The exact date on which the property, jointly owned by others unknown, was acquired is unclear, but the DEC states that it was acquired between 2015 and 2023.
The DEC said his daughter faced additional charges over the purchase of three other apartments in Lusaka that were suspected to have been purchased fraudulently.
“In addition, she was arrested for possession of an expensive house, four chicken coops and associated external works on the property,” the agency added.
All were released on bail, Lungu said, adding that they were safe at home after being questioned by DEC officials for several hours on Thursday.
Another of Ms Lungu’s daughters, Tasila, faces separate but related charges, according to the DEC.
She was ordered, through her lawyers, to appear before the DEC on Monday.
The accused did not comment on the accusations, but in a brief statement, the former president said the family would challenge them in court.
It was not immediately clear if and when they would appear in court.
Lungu announced a return to politics last October, prompting the government to withdraw their retirement benefits.
He retired from politics after losing the presidency to Hakainde Hichilema in 2021.
After six years in office, Lungu left the southern African country heavily in debt and with a precarious economy.
Several former ministers, government officials and members of Mr Lungu’s family have been on the radar of Zambia’s investigative agencies in an anti-corruption campaign launched by President Hichilema.
Mr Hichilema promised to recover all resources allegedly looted while Mr Lungu was in power.
Critics say the anti-corruption campaign is politically motivated.
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