WASHINGTON, May 20 (Reuters) - The U.S. International

Trade Commission said Monday it is investigating a complaint

filed by ArcelorMittal that Vietnamese

automaker VinFast violated its patents related to high-strength

aluminum and aluminum alloy-coated steel in imported vehicles.

ArcelorMittal in April filed a complaint with the ITC and

also filed suit against VinFast in U.S. District Court in

California, accusing the automaker of violating its patents in

its VF 8 vehicle.