Some asylum seekers arriving in the UK via small boats or the back of lorries are being electronically tagged as part of a Home Office trial programme.
Under the system, those tagged may be subject to a curfew or excluded from certain locations.
The department said the 12-month pilot, which began on Wednesday, will test whether electronic monitoring is an effective way to give immigration bail to asylum seekers who arrive in the country using "unnecessary and dangerous" routes.
The Home Office said the trial will test whether tagging aids regular contact with migrants given bail and progresses their claims more effectively.
Boris Johnson, quizzed on the policy on Saturday, said it was about ensuring "asylum seekers can't just vanish into the rest of the country".
The PM says he is 'proud' of the UK's record on granting asylum
Labour leader Sir Keir Starmer accused the government of "chasing headlines" with the plan and called for a "serious response".
"I absolutely want to see us clamp down and end the trafficking, the criminal gangs, that are running this.
"That requires a grownup, serious response, working with the French authorities, and tracking down the gangs upstream. I don't think the government's plans are going to achieve that," he said.
It comes after the European Court of Human Rights (ECHR) on Tuesday granted an injunction that resulted in a chartered aircraft to Kigali being unable to depart Wiltshire.
The ruling prompted Home Secretary Priti Patel to accuse the court, which is not linked to the EU, of being politically motivated.
Individuals tagged will have to regularly report in person to authorities, may be subject to a curfew or excluded from certain locations, and failure to comply could see them returned to detention or prosecuted.
It's not clear how many people will be tagged.
A Home Office spokesperson said: "The government will not be deterred as we plan for the next flight to Rwanda.
"We will keep as many people in detention as the law allows but where a court orders that an individual due to be on Tuesday's flight should be released, we will tag them where appropriate."
It comes after new figures revealed the number of people crossing the Channel to reach Britain this year has passed 11,000.
Analysis of Ministry of Defence data by the PA news agency shows 11,092 people have been brought to shore by Border Force or the RNLI after being rescued from small boats in the Channel, the world’s busiest shipping lane.
On Thursday, 146 people on four small boats were brought to Britain.
The daily number has been decreasing steadily throughout the week after a high of 444 on Tuesday. That was the highest number since 562 on April 14.
At least 48 people were brought ashore at Dover on Thursday, including women and children as well as adult men.
Warm weather and calm seas this week may have encouraged an increase in attempted crossings.
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Hitting out at the ECHR's ruling on Tuesday's Rwanda flight (which had, at most, seven people on board) Ms Patel told the Daily Telegraph: "The opaque way this court has operated is absolutely scandalous. That needs to be questioned.
"We don’t know who the judges are, we don’t know who the panel are, we haven’t actually had a judgment – just a press release and a letter saying we can’t move this person under rule 39.
"They’ve not used this ruling previously, which does make you question the motivation and the lack of transparency."
The ECHR protects the human rights of people in countries that belong to the Council of Europe - of which the UK is a member. It is completely separate from the European Union and consists of numbered articles protecting basic human rights.
As the Archbishop of Canterbury Justin Welby joined the debate, stating that the Church of England would oppose the move regardless of the chosen destination - ITV News' Carl Dinnen provides analysis.
Writing on Twitter, he posted: "As we've said repeatedly, the Church of England’s opposition to deporting asylum seekers without any kind of assessment or care is not because the destination is Rwanda. "We would oppose such heartless treatment wherever people were sent.
"We oppose this policy because it outsources our responsibilities, and treats vulnerable and traumatised people without any kind of dignity, compassion or justice. "This is not how God calls us to treat each other.
"We’ll continue to call for a humane and effective immigration system, and to offer our support to national and local government to deliver it. "And in parishes we’ll continue to help local communities receive asylum seekers and others arriving from overseas."