Algeria’s Supreme Court is studying corruption cases related to the former energy minister, state TV reported, as a major corruption crackdown on officials close to ousted longtime president, Abdelaziz Bouteflika rumbles on. Some of the country’s biggest businessmen have been arrested as part of an investigation into graft and state handouts. Four brothers from the Kouninef family, a family of billionaire construction magnates, as well as Algeria’s wealthiest man, Issad Rebrad, have been brought in as part of the on-going probe. Former Energy Minister Chakib Khelil is now being investigated over capital movements and contracts signed by the state energy firm Sonatrach with two foreign companies, Ennahar TV reported on Wednesday. Interim President Abdelkader Bensalah has also sacked Abdelmoumene Ould Kaddour as the chief executive of Sonatrach. He appointed the company’s head of production and exploration, Rachid Hachichi, to replace Mr Kaddour. Mr Kaddour had been close to Mr Bouteflika, who had put him in charge of overhauling Sonatrach in March 2017 after years of management upheaval, fraud scandals and red tape had deterred foreign investors. The North African oil giant is an important source of energy for European states trying to reduce dependence on Russia and it also funds a large part of Algeria's budget.<br/> Widespread demonstrations led to Mr Bouteflika stepping down from office on April 2 after 20 years in power.<br/> But the mass protest movement that forced him from office say his departure isn't enough and all those around the president must also step down to clear the way for new leadership. Few believed Mr Bouteflika has truly been in charge since he suffered a stroke in 2013 that left him in a wheelchair and he largely disappeared from public life. Instead, they blame "Le Pouvoir" or power, a shadowy group of senior intelligence officials, government ministers, members of Mr Bouteflika's family and heads of big businesses, of being the decision makers.