Walmart is closing 63 Sam's Club stores across the US, the company told Business Insider on Thursday afternoon, after reports of abrupt store closings began to emerge.

The closings will impact about 9,400 employees, a Walmart official said.

In some cases, employees were not told their store had closed before showing up to work on Thursday. Those employees learned their store would be closing when they found the store's doors locked and a notice announcing the closing, Sam's Club workers told Business Insider. At some stores, employees were turned away by police officers.

Ten of the affected stores will be turned into e-commerce distribution centers, and employees of those stores will have the opportunity to reapply for positions at those locations, a Walmart official said.

The remaining stores will stay open for several weeks before closing permanently. All of the affected stores were scrubbed from the Sam's Club website on Thursday morning.

Sam's Club CEO John Furner notified employees of the closures in a company-wide email sent Thursday.

"After a thorough review, it became clear we had built clubs in some locations that impacted other clubs, and where population had not grown as anticipated," Furner said in the email. "We will be closing some clubs, and we notified them today. We'll convert some of them into eCommerce fulfillment centers — to better serve the growing number of members shopping with us online and continue scaling the SamsClub.com business."

Sam's Club membership fees — which cost $45 annually — will be refunded to customers affected by the closings, a Walmart official said.

The closings came on the same day Walmart announced plans to raise starting hourly wages to $11, expand employee benefits, and offer workers bonuses of up to $1,000.