Migrants have been seen being picked up by drivers close to beaches in southern England after crossing the Channel illegally.
As the UK government struggles to process and find accommodation for the record influx of people making the perilous voyage in small boats, many are managing to slip through the net.
Rights groups fear people smugglers and organisers of human trafficking rings are profiting from the unregistered migrants.
While some are reported to have escaped from the Manston immigration centre in Kent, evading strict controls, and hitchhiked, others have been spotted jumping into cars, vans and even minibuses.
Prime Minister Rishi Sunak on Wednesday said that he and Suella Braverman, the home secretary, were “working day and night” to resolve the problem of illegal immigration.
Ms Braverman has been criticised for her handling of the crisis, and accused of whipping up hostility towards illegal immigrants by saying the UK is experiencing an “invasion” on its southern coast.
The vast majority of small boats crossing the Channel from northern France are intercepted by the British coastguard. Occupants are brought on board rescue vessels and taken to shore to be registered. In August, The Guardian reported that the government given more than £2.5 million ($2.86m) since the start of the year to private companies to pluck Channel migrants from boats.
But some boats reach the British coastline without the authorities noticing and migrants have been known to flee the scene before police and immigration officials arrive.
Conditions at Manston have been described as “illegal and inhumane” and some migrants are probably eager to avoid being taken there.
A woman living in a street opposite the centre said she was surprised to see migrants thumbing a lift around the corner from her home.
“I have actually seen a couple hitchhiking,” she said. “They’re not allowed out, so I don’t know how they got out.”
There has also been talk in coastal communities about migrants getting into vehicles.
Residents of Dover have described seeing cars driving “up and down” their roads.
Eighty migrants were reported to have got off two boats on a beach in October, but about 30 were unaccounted for the following day.
Two members of the group were seen hopping over a pensioner’s garden fence, The Times reported. Some migrants use their smartphones to drop digital “pins” that alert waiting drivers of their location, according to the report.
The Refugee Council called reports of migrants being picked up by motorists “very worrying” and said “we know from our work that trafficking and exploitation are serious problems”.
Residents in Aycliffe, a village near Dover, were last month advised to lock their doors after a young Albanian migrant wandered into the home of Sue Doyle, 59. The boy, thought to be aged in his mid-teens, reportedly arrived on a small boat on a nearby beach.
He asked to use her phone and demanded she drive him to Manchester.
“He walked in through my back door,” she recalled. “I was sitting in my front room and the next minute, this lad was standing in front of me.”
Ms Doyle alerted her neighbour Louise Monger, 36, who confronted the boy. She described seeing a car “driving up and down, up and down”.
She informed police who arrived shortly afterwards and picked up the boy.
Following the incident, Dover District Council sent a letter to residents at a retirement complex in Aycliffe, advising them to lock their doors.
“I'm sure many of you are aware of the problems around the estate yesterday with immigrants trying to gain entrance to people's homes,” the letter read.
“From what I understand they wanted money, phones and possibly vehicles to get away from the area.
“This is all very unnerving, as a precaution I would advise you to keep your flat doors locked just in case this happens again.”