A lorry driver has been charged with 39 counts of manslaughter over the Essex container deaths.
Maurice Robinson, 25, will appear at Chelmsford Magistrates' Court on Monday. He is also charged with conspiracy to traffic people, conspiracy to assist unlawful immigration and money laundering.
An Essex Police statement said: "The Crown Prosecution Service has authorised Essex Police to charge a man in connection with… the deaths of 39 people whose bodies were found in Grays on Wednesday.
"Maurice Robinson, 25, of Laurel Drive, Craigavon, Northern Ireland, was arrested shortly after the discovery was made at the Waterglade Retail Park.
"Three other people have been arrested in connection with this investigation.
"A 38-year-old man and a 38-year-old woman from Warrington and a 48-year-old man from Northern Ireland, who were arrested on suspicion of conspiracy to traffic people and manslaughter, remain in custody."
On Saturday, a man in his early 20s was arrested at Dublin port on an unrelated matter, and it is understood he is of interest to Essex Police over the deaths.
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An investigation was launched after the bodies of eight women and 31 men were found in a refrigerated container at an industrial park in Grays in the early hours of Wednesday.
It is not yet known when the victims entered the trailer or the exact route it travelled.
Belgian officials said the trailer arrived at Zeebrugge at 2.49pm on Tuesday and left the same day for Purfleet.
The container arrived at the Essex port at around 12.30am on Wednesday, and was picked up by a lorry cab.
The lorry left Purfleet shortly after 1.05am before police were called to the Waterglade Industrial Park at 1.40am.
Essex Police initially believed all of the dead were Chinese nationals, but the force has since said it is "a developing picture", with reports the victims may be Vietnamese.
A Vietnamese community website in the UK has given police around 20 photos of people reported missing since the discovery of the bodies.
The force said in a statement: "There are 39 victims and each appears to have a bag of some description, clothes, and other belongings.
"So far we have over 500 exhibits, including mobile phones which have to be downloaded and the interrogation of mobile phones will be important for identifying the victims but also assisting the wider investigation – this needs to be done in [a] forensic way so it will pass the evidential process for court later."
The 39 bodies have now been moved from the truck in Tilbury Docks to Broomfield Hospital in Chelmsford, where post-mortems will be carried out.
On Friday the family of a 26-year-old Vietnamese woman released text messages suggesting she had suffocated in the truck.
"I'm so sorry mom and dad… My journey abroad doesn't succeed," Pham Tra My reportedly wrote in a text message to her mother. "Mom, IRead More – Source