The first people set to be deported from the UK to Rwanda have been detained, the Home Office announced on Wednesday.
A series of raids took place across the country this week, with more operations due to be carried out in the coming weeks, the Government said.
Officials have not said how many people were taken into custody, or where they were being held before being put on planes.
It comes ahead of the Government's bid to get flights to send migrants to the east African nation off the ground by the summer, after the Safety of Rwanda Act became law last week.
Home Secretary James Cleverly said: "Our Rwanda Partnership is a pioneering response to the global challenge of illegal migration, and we have worked tirelessly to introduce new, robust legislation to deliver it.
"Our dedicated enforcement teams are working at pace to swiftly detain those who have no right to be here so we can get flights off the ground. This is a complex piece of work, but we remain absolutely committed to operationalising the policy, to stop the boats and break the business model of people smuggling gangs."
The first failed asylum seeker was sent from Britain to Rwanda under a voluntary scheme on Monday.
The unidentified man moved to Rwanda after being offered up to £3,000 financial aid and sent on a commercial flight to the central African country.
The voluntary return scheme was widened to include Rwanda as a destination earlier this year. It is separate from the Conservative Government’s plan to deport to the central African country those arriving via small boats in the English Channel.
The man is understood not to be from Rwanda originally, though the Sun newspaper, which first reported the story, said he was of “African origin”.
The failed asylum claimant took the voluntary offer some weeks ago, and is now in Rwanda it is understood, with the Sun reporting his flight left on Monday evening.
A Labour Party source said: "Is there any more blatant sign that (former immigration minister Robert) Jenrick was right about this all being symbolic before an election than this mad flurry of stories?
"The core substance though hasn't changed. This is a tiny scheme at an extortionate cost and the criminal gangs will see through this con."
