A man, 23, has been charged with human-trafficking offences in connection with the deaths of 39 Vietnamese nationals whose bodies were found in a refrigerated lorry in Britain.
Christopher Kennedy, from County Armagh in Northern Ireland, is due to appear at Chelmsford Magistrates' Court in Essex, south-east England, on Monday, police said.
Mr Kennedy has been charged with conspiracy to arrange or facilitate the travel of people with a view to exploitation, and conspiracy to facilitate the commission of a breach of British immigration law.
He was arrested early Friday on the M40 motorway.
The bodies of eight women and 31 men were found in a refrigerated trailer on an industrial estate east of London in Essex, on October 23.
The trailer had arrived on a cargo ferry from the Belgian port of Zeebrugge.
Truck driver Mo Robinson, 25, from Northern Ireland, has appeared in court charged with 39 counts of manslaughter, conspiracy to traffic people, conspiracy to assist unlawful immigration and money laundering.
Mr Robinson is due to appear at an administrative hearing at a London court on Monday.
Another man from Northern Ireland, Eamonn Harrison, 22, is facing extradition proceedings for the same charges and appeared in court in Dublin on Thursday.
The case was adjourned until December 12.
Three other people have also been arrested, questioned and released on bail as part of the investigation.
Essex Police detectives last month said they wanted to speak to two brothers, also from Northern Ireland, about the case and urged them to hand themselves in.
Many of the victims were from impoverished central Vietnam, where the main source of income is from fishing, farming or factory work.
Many families took on thousands of dollars of debt to send their children to Britain, hoping they would land good jobs and send money back to pay off the loans.
The incident has laid bare the dangers of illegal migration in Britain, where Vietnamese nationals have often found work in nail bars or illegal cannabis farms.