TOKYO — Gary Hexter resigns from his post as chief financial officer of Mazda Motor Corp. as the automaker announces a 60% drop in operating profits. Mazda Board Chairman Mamoru Takebayashi also announced plans to step down.

Hexter was sent as part of a four-man team from Ford Motor Co., which owns a third of Mazda, to help the Japanese automaker undergo a sweeping financial restructuring. He was regarded as the driving force behind Ford's restructuring efforts.

No reason was given for his departure, which is the latest in a series of top-management turnover at the automaker. Hexter's resignation comes just five months after Mark Fields, an American and Ford executive, took the helm as Mazda president.

Hexter is replaced by Robert Shanks, who currently is managing director of corporate planning and cost planning. Mazda recently announced its operating profits fell 60% in the year ended March 31.