Police are continuing to question a man over the discovery of 39 bodies in a refrigerated lorry trailer in Essex.
The lorry driver, named locally as Mo Robinson, 25, from Portadown, County Armagh, was arrested on suspicion of murder on Wednesday.
It came after the bodies of 39 people had been found in a container which had arrived in Purfleet on the River Thames from Zeebrugge, Belgium.
The suspect remains in custody for questioning by Essex Police.
Meanwhile, officers from the Police Service of Northern Ireland have carried out raids on two houses associated with the arrested man – one in Markethill, County Armagh, and another in nearby Laurelvale.
And the National Crime Agency said it had sent officers to assist and identify any “organised crime groups who may have played a part”.
Ambulance staff discovered the bodies in the refrigerated unit at Waterglade Industrial Park in Grays just after 01:30 BST on Wednesday.
The lorry and trailer left the port at Purfleet shortly after 01:05.
Eric Van Duyse, a spokesman for the Belgian federal prosecutor’s office, said that an investigation into the incident had begun.
He added: “We have no idea at the moment how long the lorry spent in Belgium, it could be hours or days, we just don’t know.”
Police said the tractor unit (the front part of the lorry) came from Northern Ireland and picked up the trailer from Purfleet.
Deputy Chief Constable of Essex Police Pippa Mills said the vehicle had been moved to a secure site at Tilbury Docks so the bodies of the 38 adults and one teenager could be “recovered while preserving the dignity of the victims”.
A spokesman for the Bulgarian foreign affairs ministry said the truck was registered in the country under the name of a company owned by an Irish citizen.
He said it was “highly unlikely” the deceased were Bulgarians.
How many migrants have died in transit?
The number of migrants who die in transit has been recorded by the UN since 2014.
Since then, five bodies of suspected migrants have been found in lorries or containers in the UK:
2014: An Afghan migrant was found dead at Tilbury Docks, Essex. He was in a shipping container, with 34 Afghans who survived.
2015: Two migrants were found dead in a wooden crate in a warehouse in Branston, Staffordshire. The crate had been sent from Italy
2016: An 18-year-old migrant was crushed while clinging to the underside of a lorry in Banbury, Oxfordshire
2016: A body was found in the back of a lorry in Kent, which had travelled from France
Data was not collected in the same way before the migrant crisis began in 2014, but such deaths are not new.
In 2000, 58 Chinese migrants were found suffocated to death in a lorry at Dover.
In 2015, the bodies of 71 people were found in an abandoned lorry on an Austrian motorway.
Police suspected the vehicle was part of a Bulgarian-Hungarian human trafficking operation.
Source: BBC
