Dozens of workers at burger chain Byron have been arrested in a swoop by immigration officials.
The Home Office said 35 people from Albania, Brazil, Nepal and Egypt were arrested for immigration offences at a number of restaurants across London.
It added that the operation was carried out with the "full co-operation" of Byron earlier this month.
The burger business carried out the correct "right to work" checks on staff members, but had been shown false or counterfeit documentation, and will therefore not face civil penalty action, the Home Office said.
A Byron statement said: "We can confirm that several of Byron's London restaurants were visited by representatives of the Home Office.
"These visits resulted in the removal of members of staff who are suspected by the Home Office of not having the right to work in the UK, and of possessing fraudulent personal and right to work documentation that is in breach of immigration and employment regulation."
The business added: "We have co-operated fully and acted upon the Home Office's requests throughout the course of the investigations leading to this action, and will continue to do so."
The burger chain said the Home Office recognises that as an employer Byron is "fully compliant with immigration and asylum law in its employment practices".
The Home Office said: "Immigration Enforcement officers carried out intelligence-led visits to a number of Byron restaurants across London on July 4, arresting 35 people for immigration offences.
"The operation was carried out with the full co-operation of the business."
A spokesman for the Home Office dismissed reports that an event was set up to lure workers to one place for immigration officials.
The hashtag #boycottbyron is trending on Twitter with people posting a variety of opinions.
Twitter user @SlyLondon wrote: "Struggling to see what Byron did wrong? Helped law enforcement arrest people suspected of using fake docs. What am I missing? #BoycottByron."
While @AbiWilks wrote: "Never, ever eating at @byronhamburgers again and would encourage others to make same decision. Craven, despicable behaviour #boycottbyron."