Truck driver Mo Robinson, 25, from Northern Ireland, has been arrested on suspicion of murder after 39 bodies were discovered in the back of a truck on an English industrial estate.
But how did they get there and when, where and how did they die?
• Police believe the container had been shipped from Zeebrugge, a port in Belgium, into the town of Purfleet near Grays in Essex, east of London.
• It is believed to have docked in the Thurrock area after 12:30am (local time) on Wednesday, October 23.
• Meanwhile, the truck is believed to have originated from Northern Ireland.
• The container and truck left the port together shortly after 1.05am Wednesday, police believe.
• Five ambulances and a car were called to the Waterglade Industrial Park in Grays shortly before 1:40am, and police were immediately notified.
• The East England Ambulance Service said it was first alerted to the scene after receiving a phone call in the early hours of the morning, but could not confirm who made the phone call.
• 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."
• Irish media reported investigations by Ireland's National Police and Security Service, the Gardai, established the truck — but not the trailer — left Dublin Port on a ferry to Holyhead on Saturday, came back to Ireland, and then left for Holyhead again the next day (October 20).
• Officers from the Police Service of Northern Ireland have raided two houses associated with Mr Robinson, the BBC reported, being in Markethill, County Armagh and in nearby Laurelvale.
• Deputy chief constable Pippa Mills from Essex Police had first told reporters police believed the lorry came from Bulgaria into the UK through the port of Holyhead, Wales on October 19. But in an update later on Wednesday, the details were changed to Zeebrugge and Purfleet.
• The truck is a red and white Swedish-made Scania Super vehicle which was emblazoned with "Ireland" on the windscreen along with a sticker reading "The Ultimate Dream".
• The Bulgarian foreign ministry said while the vehicle was registered there by a company owned by an Irish woman on June 19, 2017, it left the country the next day and didn't return.
• It was reportedly registered in Bulgaria's Black Sea port city of Varna, the ministry said.
• Road Haulage Association chief executive Richard Burnett told the Irish Mirror the container appeared to be a refrigerated unit and temperatures can dip to -25 degrees for frozen products, causing humans to "lose their lives pretty quickly".
•Mo Robinson frequently posted photos of trucks on his Instagram account, sometimes using the hashtags #fridgemen and #irishfridgemen.
• Police officers in forensic suits spent the day inspecting the large white container on the truck next to warehouses and had sealed off much of the surrounding area of the industrial site with large green barriers as they carried out their investigation.
• The truck was later driven away to a secure location at nearby Tilbury Docks so the bodies could be recovered. Police bowed their heads as it was driven past.
• The driver of the trailer wore a full forensic suit and gloves as he guided the massive vehicle.
The bodies of the 39 people are yet to be identified, including by gender, but police believe 38 adults and one teenager died.
Police said they will be working with local partners and international authorities "to gather vital intelligence and identify those who have sadly died".
Deputy Chief Constable Pippa Mills, of Essex Police, said: "In order to maintain the dignity of the people who have sadly lost their lives, we will be moving the lorry and 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 lorry and the trailer will he moved to a secure location at Tilbury Docks so the bodies can be recovered whilst preserving the dignity of the victims.
"We are yet to identify them and must manage this sensitively with their families."
Even if the trailer was not chilled the victims may have suffered agonising deaths as oxygen slowly ran out.
Sources close to Irish police said the container was normally used to transport biscuits.
Even if the trailer was not chilled the victims may have suffered agonising deaths as oxygen slowly ran out.
Aside from the truck being registered in Bulgaria, the country's Prime Minister Boyko Borissov said his country had no other connection with the deaths.
Irish Prime Minister Leo Varadkar said authorities would carry out any investigations necessary if it was established that the truck had passed through Ireland.
Jackie Doyle-Price, an MP who represents the area where the truck was found, said: "To put 39 people into a locked metal container shows a contempt for human life that is evil."
Labour leader Jeremy Corbyn was among those to speculate on the way the people had died. He said the latest deaths were an unbelievable human tragedy that needed answers. "Can we just think for a moment of what it must have been like for those 39 people, obviously in a desperate and dangerous situation, for their lives to end, suffocated to death in a container," Mr Corbyn said.
In parliament, Prime Minister Boris Johnson put aside the Brexit crisis and vowed that the people traffickers would be prosecuted to the full extent of the law. "All such traders in human beings should be hunted down and brought to justice," he said.
Home Secretary Priti Patel said: "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."
Shadow Home Secretary Diane Abbott said: "Any death under these circumstances is truly appalling. Each of the 39 will have partners, family or friends who perhaps even now don't know how their loved one died and the horrible circumstances. It's important to remember that these 39 poor, unfortunate people are the victims in this. They are preyed on by the greedy, unscrupulous and people who simply have a wilful disregard for the lives of others."
MP for the Thurrock constituency, Jackie Doyle-Price, said: "To put 39 people into a locked metal container shows a contempt for human life that is evil. The best thing we can do in memory of those victims is to find the perpetrators and bring them to justice."
This story was first published on news.com.au.
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