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June 22 (Reuters) - EV maker Lucid Group LCID.O said on Monday it would cut about 18% of its U.S. workforce and announced COO Marc Winterhoff had left the company, in a major shake-up aimed at boosting profitability amid growing competition.

The layoffs will affect Lucid's full-time employees, contractors and hourly production workers in manufacturing, and are part of a broader restructuring plan, the company said.

It also said it has scrapped the second shift at its AMP-1 factory, its primary EV production facility.

Earlier this year, Lucid suspended its full-year forecast and reported its biggest revenue miss in more than four years, as a supplier-related issue disrupted deliveries of its Gravity SUV in February.

Shares of the company were down 1.5% in premarket trading.