(ANSA) - BELGRADE, APR 30 - Several thousand steel workers from the German group ThyssenKrupp, Germany's largest steel producer, demonstrated in Duisburg against the sale of plants, fearing job cuts, according to various media outlets, including the first public channel Ard. ThyssenKrupp announced last week that it was selling 20% of its steel division to the Czech investment company "Epcg," which surprised employees and the union. (ANSA).