Police in the UK have arrested four people in connection with cyber-attacks earlier this year that affected Marks & Spencer, the Co-op and Harrods, in what police called a “significant” step.

A 20-year-old woman was arrested in Staffordshire and three males aged between 17 and 19 were arrested in the West Midlands and London on the morning of Thursday, 10 July, the National Crime Agency said.

All were arrested at their homes and devices were seized, according to police.

Morning raids

The people were suspected of Computer Misuse Act offences, blackmail, money laundering and participating in the activities of an organised crime group and remain in custody for questioning by the NCA’s National Cyber Crime Unit in relation to the retail attacks, which occurred in April.

One of the suspects is reportedly a 19-year-old male from Latvia, while the others are from the UK.

According to media reports, neighbours observed a large police operation in the quiet Staffordshire cul-de-sac where the 20-year-old woman was arrested.

Dozens of NCA officers, some wearing balaclavas, arrived in the early hours of the morning of 10 July and smashed down the door of a family home. They were later seen removing a large number of electronic devices, reports said.

Deputy director Paul Foster, head of the NCA’s Cyber Crime Unit, said specialists had been looking into the attacks since they occurred and they remain a top priority for the agency.

“Today’s arrests are a significant step in that investigation but our work continues, alongside partners in the UK and overseas, to ensure those responsible are identified and brought to justice,” he said.

He said M&S, the Co-op and Harrods had aided the investigation and hoped this would signal the importance of victims reporting cyber-crimes and engaging with law enforcement as part of the reporting process.

Disruptive attacks

The attacks on M&S and the Co-op caused significant disruption, with M&S continuing to repair its IT systems, and expecting that some will not be operational until October or November.

The Co-op, which was affected several days after M&S, had bare shelves in some stores for weeks due to computer-related logistical problems.

The company had taken its systems offline just in time to avoid ransomware being deployed on its network, which would have created even more disruption, the BBC reported.

Harrods experienced less disruption and was also forced to take its IT systems offline to mitigate the attack.

The people arrested were a 17-year-old British male from the West Midlands, a 19-year-old British man from London, a 19-year-old Latvian man from the West Midlands, and a 20-year-old woman from Staffordshire.

The NCA’s operation was supported by officers from the West Midlands Regional Organised Crime Unit and the East Midlands Special Operations Unit.