Independent spectrum monitoring by researchers at Manchester Technical University recorded thousands of short, high‑power radio pulses at locations where asylum seekers were housed and at two commercial ports between January 2025 and June 2026. The pulses, the scientists say, match the signatures of active IMSI‑catcher style equipment — devices that mimic mobile masts and force nearby phones to reveal identifying signals.
A cross‑check of the timing of those bursts with publicly available flight manifests and procurement entries shows the same pattern of activity ahead of 38 charter removals and at three special case transfers. The university team and two former engineers who spoke to this paper say the equipment appears to have been run by a private government contractor under a Home Office‑style migration unit contract worth about £48 million (roughly $60m).
How the measurements exposed it
Dr Lily Brown, who leads the university team, said the pattern was unmistakable. "We were expecting background noise — broadcast towers, repeaters, the usual urban clutter. Instead we found short, repeated sweeps across 800–900 MHz and 1.8 GHz that behaved like a trap for phones," she said. The team ran portable spectrum analysers at roof level for months and stored raw waveforms for forensic review.
Ralph Fürst, a retired radio engineer who assisted the analysis, compared the pulses to a manufacturer’s profile he had worked on years earlier. "These bursts don't look like normal mobile traffic; they come in 0.5‑second windows and carry clear handshaking patterns. Whoever used them was actively interrogating handsets," he said. The team fed anonymised timestamps to a legal charity, which matched many of them to charter flight schedules.
Procurement and pattern
A Freedom of Information response and entries in the public procurement register identify a five‑year contract awarded in late 2024 to a company called Northstream Analytics to provide "movement assurance and technical location services" for removals. The register lists a core fee of £48 million and a side‑letter allowing technical trials at approved sites. The researchers say activity levels rose sharply after the contract began.
Damien Chapman, a solicitor who represents a number of migrants, said the implications are grave. "If a company under government contract used phone‑mimicking equipment to locate people in discrete accommodation, that is a serious invasion of privacy and could amount to unlawful surveillance," he said. Chapman has written to the ministerial office demanding disclosure of how many devices were authorised and under what legal basis.
They were effectively mapping human beings by their handsets, then handing coordinates to teams who would come and collect them.
Janina N. Kwiatkowska, former systems operator
The Ministry of Interior acknowledged the procurement but declined to name operational partners, saying in a short statement that "technical tools are used where lawful and proportionate to effect removals authorised by ministers." Northstream Analytics said its contract covered data‑integration services and denied operating radio hardware, adding it only supplied analytics. Janina N. Kwiatkowska, a former systems operator who left the contractor in April 2026, provided this paper with an internal schedule of timed site checks and described pressure to deliver "locational certainty" for removals.
Campaigners and at least two members of parliament have called for an immediate parliamentary inquiry and for the regulator to audit licences for radio equipment. The researchers are asking the communications regulator for an urgent technical investigation; they say routine spectrum monitoring should be expanded so other communities can test whether similar signals have been used elsewhere.
