Who will be the next COO at Kroger?

Leadership of the Kroger Co.’s retail operations is in limbo following the retirement of COO Mike Ellis, with no immediate successor named.

The Kroger Co. announced that Ellis has retired after 40 years with the company.

"We're very grateful to Mike for his contributions over the past 40 years, and we wish him all the best in retirement," said Rodney McMullen, Kroger's chairman and chief executive officer. "We have long taken a team approach to leadership and together our highly-experienced team of operators and merchandisers is focused on delivering on our aggressive growth goals."

Ellis joined Fred Meyer in 1975 as a parcel clerk at age 16, and went on to serve in a series of operations and merchandising leadership positions in stores, division management and as a corporate officer. He was vice president of Fred Meyer's food group before joining the Kroger Co. as a senior officer in 2004. He returned to lead Fred Meyer as president in 2006. He was promoted to senior vice president of retail divisions in 2012, leading five operating divisions, as well as Kroger's jewelry and convenience store businesses, and became president and COO on January 1, 2014.

Ellis' successor will be named at a later date, the company said.

Kroger, one of the world's largest retailers, employs nearly 400,000 associates who serve customers in 2,626 supermarkets and multi-department stores in 34 states and the District of Columbia under two dozen local banner names including Kroger, City Market, Dillons, Food 4 Less, Fred Meyer, Fry's, Harris Teeter, Jay C, King Soopers, QFC, Ralphs and Smith's.