- The bodies were discovered in a container at Waterglade Industrial Estate in Grays, Essex in the early hours of Wednesday morning
- Police were alerted to the container by the ambulance service
- Everyone inside the container, 38 adults and one teenager, died
- The lorry driver, named locally as 25-year-old Mo Robinson, from Northern Ireland, was arrested on suspicion of murder
- Essex Police believe the trailer arrived via ferry from Zeebrugge, Belgium, into Purfleet on the River Thames at 00:30, while the cab originated from Northern Ireland
- Container and lorry then left the port together about 35 minutes later
- Deputy Chief Constable Pippa Mills said identifying the victims remained a "number one priority", but was expected to be a "lengthy process"
Eric Van Duyse, a spokesman for the Belgian federal prosecutor's office, said it had begun an investigation that would seek to establish whether the trailer travelled through Belgium, adding: "It seems that the lorry has been shipped from the port of Zeebrugge."
He continued: "These two elements have to be checked out for there to be an inquiry, because we have just had information to say that this has happened, but the inquiry has to establish whether this has happened or not
"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.
"We have got a good relationship with the justice and police office of Great Britain... but we have not a lot of information at this moment."
Zeebrugge's harbour master has said they find migrants trying to stowaway "every day" at the Belgian port.
Essex Police now believe the trailer containing the human cargo arrived in Purfleet docks at about 12:30 this morning, while the lorry's tractor unit originated from Northern Ireland.
- Copyright: Facebook
The 25-year-old man being held on suspicion of murder in relation to the deaths of the 39 people has been named locally as Mo Robinson, from the Portadown area of County Armagh in Northern Ireland.
He remains in custody having been arrested by Essex Police this morning.
- Copyright: BBC
The lorry and trailer have begun the journey from the Waterglade Industrial Estate in Grays, Essex, to a secure location in nearby Tilbury Docks, where the bodies of the 39 victims can be recovered.
A scene cordon will remain in place, and Deputy Chief Constable Pippa Mills thanked businesses affected by the closure for their co-operation.
Deputy Chief Constable Pippa Mills continued: "I appreciate how much attention this incident will continue to attract and the public and media appetite to understand what has happened.
"We also need to understand what has happened, and Essex Police will be working will all of our partners to ensure this happens as quickly as possible."
Deputy Chief Constable Mills continued: "This matter has attracted national and international interest and it is absolutely imperative that the operation is conducted with the utmost respect for the 39 people who have lost their lives.
"The lorry and trailer will be moved to a secure location at Tilbury Docks so the bodies can be recovered whilst preserving the dignity of the victims."
Earlier, a child placed a small bunch of flowers in tribute to those who died just outside the police cordon on the industrial estate in Grays.Copyright: Getty Images
Essex Police's Deputy Chief Constable Pippa Mills has been giving the gathered media an update on the events.
She said: "In order to ensure and maintain the dignity of the people who have sadly lost their lives we will be moving the lorry and the trailer shortly.
"Once that movement has happened we will remain here to complete some scene examinations before we can allow all the business operators back to their premises."
The Bulgarian Ministry of Foreign Affairs has said that while the bodies have not been identified "[UK] police said that it is highly unlikely that they are Bulgarians".Copyright: Getty Images
A statement said: "The Scania truck was registered in Varna [on the Black Sea coast of Bulgaria] under the name of a company owned by an Irish citizen.
"The driver of the truck, from Northern Ireland, has been arrested and is being questioned on the case by the British police.
"The truck was found earlier this morning in a parking lot in the British city [sic] of Grays."
Essex Police have now confirmed that it now believes that the trailer travelled from Zeebrugge into Purfleet, near Grays in Essex, shortly after 00:30 this morning.
Police believe the tractor unit of the lorry originated from Northern Ireland.
A statement continued: "We believe the lorry and trailer left the port shortly after 01:05. The driver of the lorry, a 25-year-old man from Northern Ireland, remains in custody having been arrested on suspicion of murder."
Police made the discovery of the bodies at about 01:40 after being alerted by the ambulance service.
A cordon remains in place on Eastern Avenue on the Waterglade Industrial Estate in Grays.Copyright: BBC
The bodies of 38 adults and a teenager have been discovered in a container lorry on an industrial park in Essex.
The vehicle, which Essex Police said they believed to be from Bulgaria, was found shortly before 01:40 BST at Waterglade Industrial Park in Grays.
Richard Smith has been at the scene:
Essex Police said earlier today that it was thought the vehicle had entered the British mainland via Holyhead in north west Wales on Saturday.
But Reuters news agency is now reporting that UK police believe the lorry travelled from Zeebrugge in Belgium into Purfleet, which is near Grays in the Thurrock district of Essex, shortly after 00:30 this morning.
Essex Police believe the lorry comes from Bulgaria and that country's foreign minister, Ekaterina Zaharieva, has tweeted: "Shocked by the terrifying news of the tragic incident in Essex.
"My thoughts and prayers are with the victims' families and friends. Hope the case is resolved quickly. Strongly condemn the human trafficking and smuggling!"
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 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 human trafficking operation based in Bulgaria and Hungary.
The Freight Transport Association (FTA) has said that it "cannot speculate on the route the driver may have taken into Essex or any other matters relating to the case".Copyright: Getty Images
However a spokesman added: "Migrants are targeting all northern European ports, not just Calais.
"FTA is calling for the government to maintain close contact with its European counterparts to ensure security systems are maintained - the safety of both the drivers and migrants must be protected.
"Our thoughts are with the families of those who have lost their lives so tragically.”
- The Independent reports that a witness had seen the lorry on Tuesday afternoon with the curtains in its cabin drawn
- The Mail Online called it "one of the UK's biggest ever murder probes"
- The Mirror noted that the lorry had a sticker on its windscreen which read "The Ultimate Dream"
- The East Anglian Daily Times reported on Holyhead being "one of the main ports for ferries from Ireland"
Home Secretary Priti Patel updated the Commons on the discovery of the 39 bodies in a container lorry in Essex.
"While the nationalities of the victims are not yet known, I have asked my officials to work closely with the investigation to provide all assistance we can," she said.
Essex Police have said investigators believe the lorry came from Bulgaria.Copyright: BBC
Speculating on the route the lorry may have taken, the chief executive of the British Road Haulage Association, Richard Burnett, said it could have travelled on a ferry from Cherbourg in northern France to Rosslare in the Republic of Ireland, before driving to Dublin to get a ferry to Wales.
He said it was "highly unlikely" the vehicle would have been physically checked if it had come from Europe.
"Because of the migrant issue at Dover and Calais, you've got far more checks that are taking place there," he said.
"You've got heartbeat monitors, you've got dogs, you've got CO2. Those checks are done as you drive through.
"Cherbourg, because it's a low-volume port, you probably won't have the same security measures that they have in Coquelles [Eurotunnel terminal] or Calais.
"If this is somebody trying to smuggle a significant number of people through then maybe Cherbourg has been picked because it's a little easier to get through."
- Copyright: Getty Images
Richard Burnett, chief executive of the Road Haulage Association, said travelling from Bulgaria to Essex via Cherbourg, Rosslare, Dublin and Holyhead would take "three to five days in total".
Essex Police has said it believes the lorry is from Bulgaria and arrived in Wales at Holyhead, on Saturday. The details of the journey have not yet been confirmed.