MASSIVE FIRE: An explosion at a Chemtool chemical plant in Rockton, Illinois, resulted in a massive fire causing heavy smoke to cover the air in the area. About 70 employees were evacuated with one firefighter transported for minor injuries. According to authorities, the fire is expected to burn for several days as the oil-based product burns off. More tonight. https://abcn.ws/3pSlal4 | ABC World News Tonight with David Muir