Two people died in an explosion Thursday at a factory belonging to Belgian metal manufacturer Umicore, dpa quoted the company confirming. The accident occurred at Umicore's site in Olen, 50 kilometres northeast of Brussels. The two people were working in a silo in which acid fluids were stored, a spokesman told dpa, adding: "For unknown reasons, there was an explosion and the silo collapsed." Umicore is a Belgian-based global materials technology group, with a background in mining. It employs more than 1,000 people in Olen, where it handles cobalt, nickel and germanium and houses a global research department, according to the company website.