A shopper has accused Sainsbury’s security of heavy-handed behaviour following an incident he says left him feeling humiliated and shaken.

Michael Vallely says he was stopped by a Mitie Security guard at Sainsbury’s in Knaphill, Woking, on Friday, December 5, 2025, after a barrier alarm sounded as he left the store.

Mr Vallely said he had earlier bought sandpaper from The Range and placed it in a disposable Sainsbury’s bag before continuing his shopping. He said he was wearing headphones and did not hear the alarm.

“As I walked out, one of my headphones fell out. When I picked it up, the guard tapped me on the shoulder and said, ‘The beeper has gone off. I need to check your bags,’” he said.

Mr Vallely said he refused, questioning the guard’s authority to search his belongings. Despite this, he alleges the guard took hold of one of his bags and repeatedly asked him to return to the store, while radioing for assistance.

“I kept asking what legal power he was using, and all he would say was, ‘Come back in the shop,’” Mr Vallely said. “I told him to let go of my bags or I would call the police.”

He claims that when the guard did not release the bag, he surrendered it in order to make the call. He also alleges the guard attempted to take hold of his second bag, which he again released.

Police later attended and returned Mr Vallely’s bags. He said a Sainsbury’s staff member apologised and offered him a £20 gift voucher, which he later returned.

“I felt humiliated,” he said. “People passing would naturally assume I had done something wrong. The level of security now in Sainsbury’s - exit barriers, alarms, and guards who act first and explain later - is alarming.

“There’s no clear signage warning customers that items from other shops may trigger alarms, and most people have no idea what their legal rights actually are.”

He added: “I slept badly for days afterwards. I believe my belongings were searched and a security tag removed without my consent. I now feel uneasy going into the store and try to avoid it.”

A Mitie spokesperson said: “We are committed to maintaining the highest standards of professionalism and apologise that on this occasion our conduct did not meet those expectations.

“As Sainsbury’s security partner, we take all customer complaints seriously and followed the agreed process when this matter was raised.

“We conducted a full investigation in December and worked closely with Sainsbury’s throughout. All security officers undertake rigorous training, and the officer in question received refresher training following the investigation.”

A Sainsbury’s spokesperson said: “Our customers are at the heart of our business, and we want them to feel safe and welcome while shopping.

“We were in touch with Mr Vallely in December to apologise for his experience. We take matters like this seriously, and our security partner investigated the incident. We also issued him with a voucher as a gesture of goodwill.”