Cincinnati-based grocer Kroger announced on Monday the abrupt resignation of its CEO Rodney McMullen, citing "personal conduct" that was inconsistent with company policy as the reason for his ousting.

Kroger Chairman and CEO Rodney McMullen is stepping down after an internal investigation into his personal conduct.

Kroger said on Monday Chief Executive Officer Rodney McMullen has stepped down from the role after a board investigation found that his personal conduct was inconsistent with the grocer's "policy on business ethics".