A statement from the prosecutor's office said Abdelmalek Sellal, in office from 2014-2017, is being investigated for "corruption and dilapidation of public funds," among other things. Sellal's incarceration came a day after former Prime Minister Ahmed Ouyahia, who was forced out in March, was sent to prison.
Algeria is in the midst of an unprecedented anti-corruption crusade, sparked by a people's revolt in February that aimed to rid this gas-rich, corruption-plagued country of its political elite and their friends, who have dominated Algerian politics since the country's independence from France in 1962.
More than a half-dozen former government ministers could be questioned by an investigative judge of the Supreme Court, which is handling the high-level corruption cases. Four former ministers, now lawmakers, are in the process of having their immunity lifted.
On Wednesday, Abdelghani Zaalane, a former public works minister and campaign manager for ex-President Abdelaziz Bouteflika, was placed under judicial control amid an investigation.
Since February, protesters have forced the resignation of Bouteflika, Algeria's long-time president, and forced the cancellation of a presidential election on July 4. The weekly protest marches were triggered by Bouteflika's bid to seek a fifth term after 20 years in power despite severe health difficulties.
Courts initially went after top industrialists, alleged to have gained lucrative contracts and other benefits via ties with ranking officials.
Said Bouteflika, the brother widely thought to be the secret power behind the ex-president, was jailed in May, along with two retired generals, once-feared intelligence chiefs.
Many have referred to Algeria's Friday protest marches as the "smile revolution" because the massive protests have remained largely peaceful despite the high stakes. Among protesters' common chants is "Everybody must be held accountable."
Still, feelings about the anti-corruption drive are mixed, with some experts suspecting it is masking a power struggle among the clans that have traditionally vied for power in Algeria.
"Personally, I consider that the moment for these arrests isn't opportune, because Algeria is living through a political crisis that must be resolved first," constitutional law expert Rachid Lerrari told the Al Bilad TV station. "I sincerely ask myself whether behind these spectacular arrests, there isn't a political settling of scores."
Elaine Ganley in Paris contributed.
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