Kansas City, Mo.-based National Beef Packing Co. announced Wednesday plans to lay off more than 400 workers as a result of losing a "major customer."

The company, which is the fourth largest beef processor in the country, will eliminate 283 postions at its plant in Moultrie, Ga. An additional 150 workers will be laid off at a plant in Hummel's Wharf, Pa., effective April 13.

Although National Beef did not mention a specific customer, the company did lose Wal-Mart as a major customer of packaged meats last year, The Atlanta Journal-Constitution reported.

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“National Beef was notified in October by one of its key customers that it would transition away from using National Beef as a supplier of case-ready beef,” the company said in a statement. “Today, there are no plans to close the Hummel’s Wharf or Moultrie facilities; however, they will begin to operate at reduced levels.”

"They gathered everyone in the lunch room Monday and told us,” a 10-year employee told The Daily Item of Sunbury, Pa. “A lot of people were visibly upset and crying. No one likes losing their jobs.”