The strike started at Boeing facilities in St. Louis; St. Charles, Missouri; and Mascoutah, Illinois, after about 3,200 local members of the International Association of Machinists and Aerospace Workers voted Sunday to reject a modified four-year labor agreement, the union said.

Over 3,200 workers have walked off the job in what marks their first strike in nearly 30 years. The affected workers, primarily based in the St. Louis region, are responsible for assembling and maintaining military aircraft,