The crime took place about 11.15am in the 2nd arrondissement and the individuals showed weapons during the robbery but did not fire them, Paris police said, adding that no one was hurt.
A De Beers Group spokesperson confirmed the robbery at the company’s store on Rue de la Paix, near Place Vendôme, and less than 300 metres from the French justice ministry.
Fabien Bogais, a representative of the Alliance police union in Paris, told reporters at the scene that four suspects arrived carrying rifles and stole hundreds of thousands of euros worth of goods within minutes.
Bogais said the robbers wore helmets but that he could not say whether they had covered their faces with clothing or balaclavas.
Authorities said substantial resources were being deployed to track down those responsible and that officers would examine the scene.
