Ten people, including two Albanian nationals, have been detained after a migrant vessel arrived at a small harbour in Cornwall.
Devon and Cornwall Police said several people were seen disembarking from the boat at Mylor Harbour, near Falmouth, before departing the area in a van on Sunday.
The force added that the two Albanians were arrested on suspicion of immigration offences.
The eight remaining arrests are understood to have been carried out in a separate police force area.
An individual believed to be under 18 was also referred to social services, the Home Office said.
The investigation is being led by Immigration Enforcement.
Devon and Cornwall Police said: “We were called shortly before 3am on Sunday September 27 following a report of a number of individuals exiting a boat at Mylor Harbour, entering a van and then leaving the area.
“Officers attended and arrested two Albanian nationals on suspicion of immigration offences.
“Immigration Enforcement is leading the investigation.”
A Home Office spokesperson said: “Officers responded quickly to an isolated and rare incident at Mylor Harbour, Falmouth.
“Ten individuals have since been arrested. Another individual understood to be under 18 was referred to social services.
“There is an ongoing investigation, and it would be inappropriate to comment further.”
On Monday, three migrants, a 10-year-old child and two women, died while attempting to cross the English Channel from France to the UK.
French authorities said that 105 people on board an inflatable dinghy were rescued after calling for assistance.
A medical team was transported to the rescue boat by helicopter to help the survivors, but the child and two women could not be saved.
Francois-Xavier Lauch, the prefect of Pas-de-Calais, said that the likely cause of death had been given as crushing.
“Apparently there was no drowning, it was likely crushing – which is just as dreadful, especially if we think of the 10-year-old child,” he said at a press conference on Monday morning.
Last week there were two uncontrolled landings on UK beaches, where migrant boats arrived without being intercepted by authorities.
Home Secretary Shabana Mahmood ordered an urgent review by the Border Security Command.
