Boeing is being hit with its second strike in less than a year after 3,200 hourly workers walked off their jobs building military aircraft.

Three Boeing defense plants face a strike as 3,200 machinists walked off their jobs. Members of the International Association of Machinists voted to strike.

Thousands of members of a union representing Boeing defense industry workers in the US states of Missouri and Illinois went on strike Monday after rejecting a contract proposal.It came hours after the union said in a statement that members at Boeing facilities in Missouri and Illinois had voted to reject a modified four-year labor agreement with Boeing.