Several US pharmacies and supermarket chains owned by Dutch food giant Ahold Delhaize have been affected by a cybersecurity incident disclosed on Friday.

Giant Food pharmacies and Hannaford supermarkets are among the impacted brands that have reported network issues as result of the incident, but other brands might be affected as well.

One of the largest food retailers in the world, Ahold Delhaize operates several supermarkets and ecommerce sites in the US, including Food Lion, Giant Food, Hannaford, Stop & Shop, and The Giant Company.

As of Tuesday, Hannaford’s ecommerce portal remains unavailable, citing technical issues with its servers. The websites of Food Lion, Giant Food, The Giant Company, and Stop & Shop remain available, with all mirroring an incident notice from Ahold Delhaize USA.

On Friday, Ahold Delhaize said that a cybersecurity issue detected on its US network prompted the implementation of mitigation measures. An investigation was immediately launched into the matter and law enforcement was notified.

“Our teams are taking steps to assess and mitigate the issue. This includes taking some systems offline to help protect them. This issue and subsequent mitigating actions have affected certain Ahold Delhaize USA brands and services including a number of pharmacies and certain e-commerce operations,” the company said.

Ahold Delhaize also said that its USA brands’ stores have remained open and serving customers while the company is working on protecting its systems and resolving the incident.

The company has not shared information on the type of cybersecurity incident it is facing, but taking systems offline is the typical response to a ransomware attack. It is unclear whether any personal information or business data was compromised in the incident.

Responding to a SecurityWeek inquiry, an Ahold Delhaize spokesperson shared no additional information on the incident beyond the Friday announcement.

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