Police have launched a manhunt for a number of suspects after R300m worth of jewellery was stolen from a warehouse in Johannesburg belonging to Richemont - which is chaired by Johann Rupert - the Sunday Times has reported.According to police, an unconfirmed number of suspects robbed the jewellery warehouse in Bryanston on Friday night.Police spokesperson Captain Mavela Masondo reportedly said that the suspects were armed with pistols and reportedly entered the office park and held the guarding security guards at gunpoint.The suspects then reportedly proceeded to the premises and broke the security doors and took an undisclosed amount of jewellery, Masondo reportedly said. A case of business robbery has been opened and a manhunt has been launched to find the suspects.Sunday Times reported that the warehouse belongs to RLG Africa, which is a subsidiary of Rupert's company, Richemont.According to the paper, diamond necklaces, watches and earrings worth millions, meant for sale in South Africa, was being stored at the warehouse.According to Forbes, Rupert is chairman of Swiss luxury goods firm Compagnie Financiere Richemont. The company is best known for the brands Cartier and Montblanc.He has a reported net worth of $6.2 bn (R94.5bn). Rupert was in the news recently when it came to light that he had met with EFF deputy head Floyd Shivambu at an exclusive wine estate in Stellenbosch to discuss business, according to a book by News24 assistant editor Pieter du Toit, titled The Stellenbosch Mafia: Inside the Billionaire's Club. News24 reported that despite the party and Shivambu's ideological stance on white monopoly capital and Rupert, Shivambu had asked the Remgro chairperson and the founder of FirstRand Bank, Gerrit "GT" Ferreira, for assistance to build a hospital in Limpopo.Shivambu has denied this.