More than two thousand people had said on Facebook they would attend the protest at the High Holborn branch.
It has been arranged in response to widespread claims that Byron acted in conjunction with the Home Office to organise a sting operation on 4 July against 35 members of its staff who had breached immigration rules.
Right now in front of Byron in Holborn! Protest against inhuman action against its own workers. pic.twitter.com/oFlDEdtVUq— Marcin Hordyniec (@marchingMarcin) August 1, 2016
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The protest has been organised by the Unite Hotel and Restaurant Workers Branches, the United Voices of the World Union, London Latinxs, Black Dissidents, London IWW, Lesbians and Gays Support the Migrants, South London Solfed, War On Want and Global Justice Now.
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In a tweet this evening, Byron reiterated its previous statement about the Home Office investigation:
Here's a statement from us regarding the recent Home Office investigation. pic.twitter.com/QSNO1tgvk1— Byron (@byronhamburgers) August 1, 2016
Both Byron and the Home Office have said several of the group's restaurants were visited by Home Office staff.
Neither has confirmed reports that a training day was organised in which workers were brought to London and then arrested by Home Office staff, as has been claimed.