BENTONVILLE, Ark. (KNWA/KFTA) — Walmart customers took to social media to speak out about an email they received containing a racial slur, prompting the big box store to issue a statement Monday blaming an “external bad actor.”

The email the retail giant sent to NewsNation affiliate KNWA/FOX24 reportedly contained the slur in place of some customers’ names.

Walmart spokesperson Payton McCormick said the emails were not sent by anyone affiliated with the company.

“We discovered that an external bad actor created false Walmart accounts with obvious intent to offend our customers. We were shocked and appalled to see these offensive and unacceptable emails,” McCormick said. “We’re looking into our sign up process to ensure something like this doesn’t happen again. We’re also looking into all available means to hold those responsible accountable.”

One Twitter user who called the email “disturbing,” shared a screengrab of the offensive message:

The Bentonville-based retailer has not said how many people received the offensive email, but that they are taking actions to prevent similar situations from happening in the future.