The brother of ousted Algerian President Abdelaziz Bouteflika and two former intelligence chiefs have been arrested, reports say.
The men were apparently were taken into custody on Saturday after an "investigation into their activities", local media report.
It comes after weeks of mass protests calling for the complete overthrow of the country's elite.
A number of high-profile figures have become subject to investigation since.
Said Bouteflika and Generals Bachir Athmane Tartag and Mohamed Mediene are due to appear before a military court on Sunday, Algerian news website ALG24 reports.
Mr Bouteflika's brother was considered by many as Algeria's de facto leader since his brother suffered a stroke in 2013.
The head of the army, Lt Gen Gaid Salah, had previously accused Mr Mediene, better known as General Toufik, of conspiring against the army and the people.
Mr Tartag succeeded Mr Toufik in 2015, but was himself dismissed on 5 April, shortly after Mr Bouteflika stepped down.
The former president, who had been in power for 20 years, resigned last month after months of anti-government protests.
Abdelkader Bensalah, the former head of the Senate, took over as interim leader and has vowed to hold free elections in July.
However, demonstrators also want him to resign and have continued to call for more radical change.
Many have called for the downfall of "Le Pouvoir", or the establishment, meaning that all those around the former president should also go.
About 70% of the country's population is under 30, and youth unemployment is high.
Lt Gen Salahsaid last month that some among the ruling elite should be questioned over alleged corruption.
A number of high-profile figures, including billionaires and a former prime minister, have been arrested since.