CINCINNATI— Rodney McMullen has resigned as chairman and chief executive officer of The Kroger Co. following an internal investigation into his “personal conduct,” according to the company. The company said McMullen’s actions were unrelated to the business, but inconsistent with the retailer’s business ethics policy.

“On Feb. 21, the (Kroger’s) board was made aware of certain personal conduct by Mr. McMullen and immediately retained outside independent counsel to conduct an investigation, which was overseen by a special board committee,” the company said. “Mr. McMullen’s conduct is not related to the company’s financial performance, operations or reporting, and it did not involve any Kroger associate.”

Kroger’s board of directors has formed a search committee to conduct a search for Kroger’s next CEO. In the meantime, Ronald Sargent, a Kroger board of director since 2006 and the former CEO of Staples, Inc., will serve as interim CEO.

“As interim CEO, I am committed to working alongside our proven and experienced management team and dedicated associates to ensure Kroger continues providing exceptional value for our customers,” Sargent said.

“Over the years, Ron has played an integral role in the development and approval of Kroger’s strategy, which has led us to the position of strength where we are today,” said Mark Sutton, Kroger’s newly appointed lead independent director.