Angolan authorities arrested and charged Mr Augusto da Silva Tomás, a former transport minister, over corruption allegations.
Mr Tomás was arrested on Friday over crimes of corruption and embezzlement and is confined at São Paulo prison.
He is the first top government official arrested over corruption allegations since independence from Portugal in 1975.
Mr Tomás served as a government official under Dos Santos’s government and was fired in June, 2018 by President João Lourenço.
In 2008, former president José Eduardo dos Santos appointed him as the country’s transport minister after serving as the state secretary for the state-owned business sector.
He also served as economy and finance minister (1995-1996), Cabinda province governor (1991-1995), industry and commerce deputy minister (1990-1991), and industry deputy minister (1989-1991).
President Lourenço took over from José Eduardo dos Santos in August, following an election, marking the end of a 38-year reign.
Mr Lourenço has fought against corruption and fired government officials linked with his predecessor.
He has fired Ms Isabel dos Santos, dos Santos’s first daughter from the top job at Sonangol, the state-owned oil company as well as her half-brother José Filomeno dos Santos "Zenu” from the leadership of Angola's sovereign wealth fund.
Ms Santos now faces several graft investigations while his brother has been charged with misappropriating public funds.
On Wednesday, Angolan prosecutors dropped corruption charges against a former army chief of staff Geraldo Sachipengo Nunda who was sacked in April by Mr Lourenço.
According to the country’s top court, the charges against General Nunda were dropped because of lack of evidence.
Eight other accused, including a spokesperson for the ruling party, four Thai nationals, a Canadian and an Eritrean national were placed under house arrest in connection to a $50 billion fraud.
Their trials are expected to begin before the end of the month.