Woman and three teenagers arrested over M&S, Co-op and Harrods cyber attacks

Four people have been arrested by police investigating cyber attacks targeting M&S, Co-op and Harrods.

A 20-year-old woman and two men, both aged 19, and another man aged 17, were detained in London and the West Midlands this morning as part of a National Crime Agency (NCA) operation.

They were arrested at their homes on suspicion of Computer Misuse Act offences, blackmail, money laundering and participating in the activities of an organised crime group.

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Electronic devices were seized from the suspects and are currently being analysed by forensic experts.

M&S halted online orders, and shelves were empty in shops after the cyber attack on the retailer earlier this year.

The initial hack into the retailer's systems took place in April through "sophisticated impersonation" involving a third party.

Disruption is expected to continue at the retailer until the end of this month.

The Co-op and Harrods were also subsequently targeted by hackers.

Paul Foster, head of the NCA's National cybercrime unit described the arrests as a "significant step" in their investigation, which remains "one of the Agency's highest priorities".

He added: "Our work continues, alongside partners in the UK and overseas, to ensure those responsible are identified and brought to justice".

The National Crime Agency is keen to "signal" to "future victims" the "importance of seeking support and engaging with law enforcement", stating that "the NCA and policing are here to help".

The NCA has also thanked M&S, Co-op and Harrods for their support in their investigations.

The arrests, which took place early on Thursday morning, were supported by officers from the West Midlands regional organised crime unit and the East Midlands special operations unit.

Earlier this week, the chairman of M&S told MPs that the hack had been "traumatic" and like an "out-of-body experience".

Archie Norman, however, refused to be drawn on whether the retailer had paid any ransom.

"We are not discussing any of the details of our interaction with the threat actor, including this subject, but that subject is fully shared with the NCA," he said.

It is estimated that the cyber attack will cost M&S up to £300m this year.

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Days after M&S was attacked, the Co-op was targeted and forced to shut down some internal systems.

Harrods was then hacked, and also had to shut some systems despite its website and shops continuing to operate.

Of those arrested, a 17-year-old British male and a 19-year-old Latvian male were from the West Midlands.

A 19-year-old man was from London and a 20-year-old woman from Staffordshire.

An M&S spokesperson said, "We welcome this development and thank the NCA for its diligent work on this incident."