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.

Several thousand workers at three Midwest manufacturing plants where Boeing develops military aircraft and weapons went on strike early Monday, potentially complicating the aerospace company's progress in regaining its financial footing.

After rejecting the company's second proposed contract, union members in the St. Louis area began striking Monday. They said they will not stop until they receive a fair deal.