All Pepsi employees, including 55-year-old Daryl Smith, were informed of the closure at about 5:45 a.m. ET around the same time that Teamsters Local 727 received written notice from Pepsi attorneys.

Pepsi shuttered its South Side plant without notice Monday morning and laid off at least 79 employees. Workers showed up at the plant as usual early Monday only to learn they had been let go and ...