Guidance for immigration enforcement officials published on 8 October, and a data protection impact assessment released later that month, describe a programme to locate people without legal status.
The papers indicate that people liable to detention under immigration law, those who have failed to comply with conditions of entry or stay, visa overstayers and people who entered without leave could later be added. Overstaying and entering without leave are civil, not criminal, matters.
Earlier trials focused on people travelling from Ireland through the common travel area in breach of deportation orders or wanted on a warrant for an immigration-related criminal offence.
Possible deployment sites have been widened to include proactive use at transport hubs and at specific events expected to raise footfall, though no places were named.
The Home Office has set out plans to use live facial recognition cameras for general immigration enforcement, including non-criminal offences, according to new official documents.
The documents follow earlier reporting that the Home Office kept using an artificial intelligence facial-age estimation tool after it had misidentified child migrants as adults.
Officials say locating undocumented people with the technology would cause less disruption to the public than repeated visits to homes or workplaces.
A list of higher-risk uses includes locations with heightened community sensitivity.
No one under 18 will be placed on a watchlist, the policy document states.
A Home Office spokesperson said the department was considering further trials by immigration enforcement officers and was actively exploring the benefits, implications and future use of the technology.