United Natural Foods Inc., the primary food distributor for Whole Foods, was hit with a cyberattack that may leave some grocery store shelves empty.

The food company said Monday it became aware of “unauthorized activity” on some of its IT systems, prompting the supplier to take some services offline.

With the systems down – and no immediate time for them to be back up and running – stock on Whole Foods’ shelves may soon be sparse. The computer system was used to connect customers – such as Whole Foods – to the supplier and get deliveries of goods.

A Whole Foods spokesperson told The Independent that they are “working to restock our shelves as quickly as possible and apologize for any inconvenience this may have caused for customers.”

In an SEC filing, the food company said it noticed the unusual activity last week and immediately implemented containment measures. The company said it notified law enforcement and is currently investigating the incident.

“We are assessing the unauthorized activity and working to restore our systems to safely bring them back online,” the company said in a statement. “As we work through this issue, our customers, suppliers, and associates are our highest priority. We are working closely with them to minimize disruption as much as possible.”

Last year, the food company and Whole Foods signed an eight-year extension of their deal to be the supermarket’s primary distributor, according to Axios.

Issues with deliveries from the supplier were detailed in a Reddit post.

“We got our Saturday truck at 2 a.m. Sunday morning, with no way to scan it in to the store receiving tool and none of the typical UNFI paperwork. They are saying no cycle counts or orders until further notice. This seems bad, to say the least,” the poster wrote.

Someone claiming to be a food company employee commented that they “literally cannot do anything network related.”

“At a complete standstill. This is catastrophic to the business. This is a company-wide issue that affects business at all levels. This is really some crazy s***,” the employee wrote.

Another person claiming to work for United Natural Foods Inc. said work has been canceled the last two days.

“Apparently our whole system is down right now. We haven’t been told everything, just that we can’t come into work,” they wrote.