Immigration officials raid office of upmarket lifestyle magazine Tyler Brûlé spoke of the "extraordinary" scenes when the officers told staff at the magazine, which employs 140 people in the UK, that they needed to check their visas. He joked that the officers must have suspected the magazine of smuggling staff in through a secret tunnel. The Home Office said it had no record of the incident, which Mr Brûlé said happened last month at its offices near Oxford Street. But civil liberties groups said the tactic was further evidence of Border Force officials taking tougher action away from ports and airports to combat illegal immigration. Mr Brûlé said: "We have of course applied for a number of visas, everything is very legit. But they must obviously think we have some secret tunnel under the building where we bring in other workers from overseas. What happens is they come into the building, three officers, they say they want to check everyone's visas and they send everybody home. We have 140 people in our offices in London. He told the Edelman Crystal Ball Breakfast, a forecasting event: "I thought this could be some kind of positioning exercise, that someone goes back to the Home Office and says: "At least we did that, we ticked that part of W1 [postcode]." Shami Chakrabarti, the director of Liberty, said such raids were happening more frequently. "Try running a restaurant to find out what's happening," she told the same event. This is quite new and it's probably going to get worse in the run-up to the election. She claimed it was part of a "really nasty" new tactic which amounted to "bringing border controls to the streets." A Home Office spokesman said: "We have looked into this ... there is nothing on our system about an immigration raid on this address whatsoever." He said Border Force officers would not send employees home to produce their visas. Mr Brûlé declined later to provide more information about the episode. However, two other magazine staff members confirmed it had taken place. One said: "A lot of the team were in the office when [the officers] arrived." The reported raid follows the storm over a Home Office van which toured inner London boroughs in the summer bearing an advert that urged illegal immigrants to "go home," and spot-checks by border force officers at railways stations in areas with high ethnic minority populations. In October all the businesses in London's Chinatown shut and staff walked out in protest over a series of recent raids. Mr Brûlé, a Canadian entrepreneur who also founded Wallpaper* magazine, launched Monocle in 2007. It has bureaux in Tokyo, Hong Kong, New York and Toronto, as well in Marylebone, London. Mark Harper, the Immigration minister, has hit back at Lance Batchelor, the chief executive of Domino's Pizza, who said he had hire outside Europe to fill posts. "He should probably pay his staff a little more and he might find them easier to recruit," Mr Harper told MPs.