A Greensboro call service center is permanently closing and laying off 685 people.

NCO Customer Management has notified the N.C. Commerce Department that that layoffs will begin after May 7 and take place in stages until the facility shuts down on Aug. 31.

The company said it's closing because of "client mandated business decisions and requirements," but did not identify which clients are no longer using NCO's call center. A call to the company was not immediately returned.