More than 3,200 union members who assemble Boeing's fighter jets in the St. Louis area and Illinois went on strike on Monday after rejecting a second contract offer the previous day.

Boeing union workers who assemble fighter jets strike in two states following rejection of contract offering 20% general wage increase and $5,000 bonus.

Boeing warned over the weekend that it anticipated the strike after workers rejected its latest offer, which did not further boost the proposed wage hike.