The pair, a 30-year-old Vietnamese national and a 50-year-old British national, were detained yesterday (8 October) after the car they were travelling in was stopped in the Grange Road area of Croydon, as part of a National Crime Agency operation.
They were held on suspicion of assisting in the facilitation of illegal immigration.
The 50-year-old has since been released under investigation, while the 30-year-old, who is alleged to have played a key role in the criminal enterprise, remains in custody.
The organised crime group under investigation are alleged to be involved in the smuggling of Vietnamese migrants into the UK in lorries and other vehicles.
Two other Vietnamese men who were in the same car at the time of the arrests were also detained on suspicion of being in the UK illegally.
NCA investigators believe they had recently been moved into the UK by the crime group. They will now be dealt with by the immigration authorities.
The investigation is being led by the Project Invigor organised immigration crime taskforce.
NCA Regional Head of Investigations Andrea Wilson said:
“These arrests are a very significant moment in what has been a long-running investigation into the illegal transportation of migrants to the UK.
“Working with our partners in the Invigor taskforce we are determined to do all we can to disrupt and dismantle criminal groups involved in people smuggling.
“We have seen the callous nature of how these groups operate. They don’t care about putting people in extremely dangerous situations to cross the Channel, whether that be in the backs of lorries or in small boats. In their minds migrants are a commodity to be profited from.
“Our investigation into this network continues.”
Project Invigor is led by the NCA but also comprises Immigration Enforcement, Border Force, the CPS and the Home Office.