Marks and Spencer's retail boss has warned crime is getting "more brazen, more organised and more aggressive" after a week plagued by antisocial behaviour.
Retail director Thinus Keeve hit out at the government and London mayor Sadiq Khan in a letter posted to the supermarket's website.
"Without a government seriously cracking down on crime and a mayor that prioritises effective policing, we are powerless," he said.
Following unrest on Saturday, about 100 officers responded to antisocial behaviour in Clapham, south London, on Tuesday, four of whom were assaulted, along with one member of the public.
Scores of teenagers and young adults were participating in so-called "link-ups" – using social media apps including TikTok and Snapchat before surging into shops.
M&S was reportedly one of the stores targeted.
Mr Keeve went on: "It is becoming more brazen, more organised and more aggressive."
"We need a stronger, faster and more consistent police response, using tools that already exist to target repeat offenders and crime hotspots," he said, adding: "It's a clear ask: support our police. Help them show up in our communities when and where we need them.
"Give them the resources they need to tackle crime effectively, and ensure they work with retailers to consistently use the tools we've developed to share data and actively target offenders."
'None of us believe crime is falling'
He also questioned claims that crime rates are falling in the capital.
He said: "I keep hearing crime is falling, especially in London - something none of us believe, and very few people working in retail would see."
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M&S chief executive Stuart Machin has written to the Home Secretary Shabana Mahmood following the scenes over the weekend, which Sir Sadiq condemned as "utterly unacceptable".
The London mayor said "the culprits will face the full force of the law" and police were working with social media companies to try to clamp down on "viral online content which promotes violence and theft".
'Part of the broader picture'
Speaking to Sky News, M&S head of external affairs Adam Hawksbee said the Metropolitan Police's response to the chaos was "excellent".
But he said the incident in Clapham is "just part of the broader picture", with 1,600 retail workers a day experiencing violence and abuse.
"Some incidents will be serious and organised crime, and others will be individuals that are under the influence of alcohol and drugs. And this can be really scary, both for our colleagues working in the store and for the security guards," he said.
"We've had ammonia thrown in the face of one of our security guards. In the last week, we've had a store manager headbutted and these incidents are not isolated to us at M&S. They're true across the retail sector and that's why we feel like we needed to speak out."
Meanwhile, police in Rochdale issued a 48-hour dispersal order following anti-social behaviour.
(c) Sky News 2026: M&S boss issues stark warning over worsening crime
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