The disruption being caused by the wave of cyber attacks on UK retailers has been apparent for weeks. Empty shelves, cancelled online orders, the data of millions of customers stolen.
What has been much less clear is who is responsible, with the companies and authorities only giving limited details.
But, now - in their first interview - the National Crime Agency (NCA) has indicated where their suspicions lie, and named the notorious cyber-criminal collective Scattered Spider as a key part of their investigation.