More than 3,200 Boeing employees at defense division factories in the St. Louis area could walk off the job Sunday, halting production of the aerospace company’s fighter jets.

U.S. planemaker Boeing sent a new contract offer on Thursday to the union representing roughly 3,200 factory workers at Boeing's defense division, mostly in the St. Louis area. It contains some minor compensation changes that would benefit senior union members,

Boeing is facing yet another challenge as 32,000 members of the IAM union are threatening to strike this month if a deal isn't reached on a new contract with the company.