The PSNI has searched two homes in Co Armagh overnight after 39 bodies were found in a lorry container in Essex.
Portadown man Mo Robinson, 25, is being questioned by police in Essex on suspicion of murder in relation to the discovery in the early hours of Wednesday, Belfast Live reports,
Pictures of him driving the lorry have emerged.
The bodies of 38 adults and a teenager were discovered in a refrigerator unit on the back of the lorry. It is thought they may have frozen to death or suffocated.
Efforts are ongoing to identify the bodies.
Police say the trailer containing the remains originated in Belgium, but they don't believe the victims are from the country.
Belgian media report that the country's federal prosecutions office said late on Wednesday it too has opened an investigation.
It is not know at this stage how long the container had remained in Belgium, or what its precise route was.
Police now say the lorry and trailer left the port at Purfleet shortly after 1.05am.
Essex Police were alerted to the bodies by the ambulance service at 1.40am on Wednesday.
An international hunt for the people-smuggling gang that sent them to their tragic ends has been launched after they were found at Waterglade Industrial Park in Eastern Avenue in nearby Grays.
