Auto parts supplier Tower Automotive, which declared bankruptcy earlier this year, is reported to be closing three facilities and laying off 800 workers as part of a restructuring.

According to the Associated Press (AP), Tower said it would close plants in Bowling Green, Kentucky, Belcamp, Maryland, and Corydon, Indiana, by June 30 and also will lay off employees at a plant in Granite City, Illinois.

"As we go through our restructuring process, we must take all necessary actions to make Tower the most efficient and competitive company possible," Bill Pumphrey, Tower's president of North American operations, said in a statement cited by the news agency.

Tower isn't revealing how much it expects to save from the closures, spokesman Doug Morris told AP.

Morris reportedly said the Belcamp plant supplies frames to a General Motors plant in Baltimore that is closing next month, the Corydon plant does welding, riveting and assembly on parts for the Ford Explorer sport utility vehicle, which has seen sales fall by more than 25% so far this year, and the Bowling Green plant supplies two other Tower facilities.

The Associated Press noted that Novi, Michigan-based Tower filed for bankruptcy protection in February, citing lower auto production volume and high steel prices - the company reported $US787.9 million in assets and $1.3 million in debts at the time.

Tower is one of the largest auto suppliers to declare bankruptcy with more than 12,000 employees worldwide, AP added.