A former Algerian police chief once considered a pillar of the regime of ousted president Abdelaziz Bouteflika has been summoned for questioning about allegations of corruption, state media said Sunday.

Since Bouteflika resigned in early April after weeks of mass protests against his rule, several regime officials and businessmen who were close to him have been sacked or detained over alleged graft.

General Abdelghani Hamel, the former police chief once tipped as Bouteflika's successor before he was fired by the veteran leader in June 2018, is due to appear in court Monday with one of his sons, state radio said.

They are expected to be questioned as part of a judicial inquiry into "illegal activity, bribery, embezzlement of funds and abuse of power," according to state television.

Since Bouteflika's ouster investigators have cracked down on alleged graft, zeroing in on the activities of prominent politicians and businessmen as they try to clear away two decades of cronyism under the former president.

High-profile figures who were targeted over the past week include the North African country's richest man, Issad Rebrab, who was detained Monday on allegations of false customs declarations.

The head of the vast state oil firm Sonatrach, Abdelmoumen Ould Kaddour, was fired and replaced on the orders of interim president Abdelkader Bensalah.

Four brothers from the influential Kouninef family, close to Bouteflika's brother Said, were also arrested last Sunday over alleged non-compliance with state contracts, according to state media.

A magistrate has also summoned for questioning Finance Minister Mohamed Loukal and former prime minister Ahmed Ouyahia in connection with alleged misuse of public funds.

Late last month top Algerian businessman and Bouteflika backer Ali Haddad was arrested as he tried to cross the border into Tunisia with two passports and undeclared currency.