UK supermarket giant Tesco has restored access to its website and app after an outage struck the service on Saturday, preventing customers from ordering or cancelling deliveries until Sunday evening.
In a statement to The Guardian, Tesco said that "an attempt was made to interfere with our systems, which caused problems with the search function on the site."
The retailer, whose 1.3 million online orders per week account for nearly 15% of its UK sales, said there was no reason to believe the attempted interference impacted customer data.
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Tesco confirmed on Sunday evening that its website and app were now restored, but that it was using a virtual waiting room to handle a backlog in orders.
"Our groceries website and app are back up and running. To help us manage the high volume we're temporarily using a virtual waiting room. We're really sorry for any inconvenience and thank you for your patience," Tesco said on Twitter.
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