Kroger Co. replaced Chief Executive Officer Rodney McMullen following an investigation into his personal conduct, casting a shadow on the supermarket operator’s path forward following a failed deal and a string of management departures under the longtime leader.

Kroger CEO Rodney McMullen is resigning immediately from the grocery store chain following an investigation that found his personal conduct was “inconsistent” with the company’s ethics policies.

Board member Ronald Sargent will serve as Chairman of the Board of Directors and interim Chief Executive Officer