Getty ImagesThe luxury department store Harrods says it is the latest retailer to have been targeted by a cyber attack.
The firm said it had "restricted internet access at our sites" following an attempt to gain access to its systems.
It comes the day after the Co-op shut down parts of its IT systems to fend off a hack, while Marks & Spencer continues to deal with a cyber attack that has cost it millions of pounds in lost sales.
Harrods said its flagship store remained open, and it continues to operate its online sales.
Customers are being asked to "not do anything differently at this point".
A statement from Harrods read: "We recently experienced attempts to gain unauthorised access to some of our systems.
"Our seasoned IT security team immediately took proactive steps to keep systems safe and as a result we have restricted internet access at our sites today.
"Currently all sites including our Knightsbridge store, H beauty stores and airport stores remain open to welcome customers. Customers can also continue to shop via harrods.com.
"We are not asking our customers to do anything differently at this point and we will continue to provide updates as necessary."
It comes as M&S has seen its operations severely hampered by a cyber attack the firm disclosed last week.
Customers are still unable to place online orders and shelves have been left empty in some stores.
The police are investigating.
Meanwhile, the Co-op said on Wednesday it had shut down parts of its IT systems in response to hackers attempting to gain access.
On Thursday, it emerged staff were being ordered to keep their cameras on during remote work meetings, and verify all attendees.
Experts say that indicates the company suspects hackers may be lurking in calls.
It is not known if the three incidents are connected.
But it is believed M&S was attacked with ransomware.
This is a type of malicious software used to scramble important data or files after gaining access to computer systems, essentially locking them away unless a ransom is paid.
Security experts told the BBC on Tuesday a ransomware group which goes by the name "DragonForce" was behind the attack.
The retailer has not commented. The co-op has not given any details of the nature of cyber attack made against it.
