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.

T hree Boeing defense plants, including those at a manufacturing plant at MidAmerica Airport in Mascoutah, face a strike as 3,200 hourly machinists walked off their jobs. Members of the International Association of Machinists voted to strike at about noon Monday.

Roughly 3,200 workers are striking at sites in Missouri and Illinois. Members of the labor union representing the workers rejected a modified contract offered by Boeing last week.