KELLER, Texas -- Hundreds of workers at a Keller warehouse that supplies Kroger grocery stores have been told they may lose their jobs in the middle of the holiday season.

The warehouse is operated by SouthStar LLC, a Kroger contractor. In documents filed with the Texas Workforce Commission, the company gave notice that it expects employment of all 690 employees will cease starting Dec. 10. The letter to the commission said the sudden decision is a result of Kroger's "short and unexpected notice" that it was terminating the relationship.

In a statement, Kroger said the massive warehouse is not closing. They are changing contractors, and Penske will now operate the warehouse.

Employees say they have been left in the dark through the process.

"Basically, we were blindsided," said Gabriel Smith. "We need to know what's going on."

Workers say SouthStar LLC was one of the few places hiring people with a criminal record. Smith said he has worked in the warehouse the last five years, after serving time for aggravated robbery. He said he got the job after completing a program, but now he's not sure whether he will have a job when Penske takes over management.

"Nobody wants to lose their job around Christmas time," he said.

A Penske spokesperson said they intend to recruit existing employees from the warehouse, in addition to outside candidates. The company is currently negotiating with labor unions that represent the warehouse workers. Penske would not say exactly how many jobs they will fill or whether they will re-hire felons.