A 36-year-old man has been arrested on suspicion of manslaughter following the deaths of 39 Vietnamese people in a lorry trailer found in Grays, Essex.
The man, from Purfleet, Essex, was arrested on Monday morning at a property in Dalston, east London, Essex Police said.
He was also arrested on suspicion of conspiracy to traffic people and conspiracy to assist unlawful immigration.
The man remains in custody for questioning.
Ten teenagers, including two 15-year-old boys, were among the 39 people whose bodies were discovered in the trailer in the early hours of October 23.
Emergency services were called to an industrial estate in Grays shortly after the lorry arrived on a ferry from Zeebrugge in Belgium.
Lorry driver Maurice Robinson, of Craigavon, County Armagh, pleaded guilty at the Old Bailey on Monday to conspiring with others to assist illegal immigration between 1 May 2018 and 24 October 2019.
Christopher Kennedy, of Darkley, County Armagh, also appeared at Chelmsford Magistrates' Court on Monday charged with human trafficking offences.
No pleas were entered.