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UAW Local 2093 members launched an unfair labor practice strike at Dauch Corp.'s Three Rivers, Michigan plant at 12:01 a.m. Monday after the company failed to offer a new contract before the expiration deadline, the union said.

The plant, which produces axles for GM's midsize and full-size pickup truck lines, employs roughly 1,000 union workers, Reuters reported. Additional picket lines began at 6:00 a.m. GM said it was watching the situation and assessing any potential impact.

The union is demanding wage increases after workers accepted pay cuts to keep the plant open during the 2008 financial crisis. Before the 2008 crisis, workers could earn up to $29 an hour, but pay has since been capped at $22 an hour once a five-year progression is complete — and when adjusted for inflation, the union says, real wages have been cut roughly in half compared to pre-recession levels. In early May, workers voted 98% in favor of authorizing a strike if needed.

UAW President Shawn Fain used a Sunday livestream to announce the walkout, declaring: "For 18 years, these members have built you an empire of profit while getting treated like dirt. They've taken wage cuts, benefit cuts, they poured their souls into this plant," according to Reuters.