Police investigating the deaths of 39 people in a truck near London said they had arrested a man and a woman on Friday on suspicion of human trafficking amid signs that some of the dead may be Vietnamese.
As forensic experts began the process of identifying the victims, a human rights activist said at least one of them might have been a Vietnamese woman.
Police have said they believe the dead were Chinese but Beijing said the nationalities had not yet been verified.
“We hope that the British side can as soon as possible confirm and verify the identities of the victims, ascertain what happened and severely punish criminals involved in the case,” Chinese Foreign Ministry spokeswoman Hua Chunying told a daily news briefing.
Police said they had detained the man and woman, both aged 38, in Warrington, northwest England, on Friday on suspicion of conspiracy to traffic people and of 39 counts of manslaughter.
The 25-year-old truck driver remains in custody after being arrested on suspicion of murder following the discovery of the bodies in the back of his refrigerated truck in the early hours of Wednesday.
He has not been formally identified but a source familiar with the investigation named him as Mo Robinson from the Portadown area of Northern Ireland. Detectives will decide later whether to charge him with an offence, release him or ask a court for more time to question him.
The victims – 31 men and eight women – are being moved to a hospital mortuary from a secure location at docks near the industrial estate in Grays about 20 miles (30 km) east of London where the bodies were found.
Post-mortem examinations were beginning to determine how exactly they died while forensic experts sought to identify the deceased.
Hoa Nghiem from Human Rights Space, a civic network based in Vietnam, said at least one of the deceased might have been Vietnamese.
Pham Thi Tra My, 26, sent a text message to her mother saying she could not breathe at about the time the truck container was en route from Belgium to Britain, Hoa said.
“I’m sorry Mom. My path to abroad doesn’t succeed. Mom, I love you so much! I’m dying bcoz I can’t breath … I’m from Nghen, Can Loc, Ha Tinh, Vietnam … I am sorry, Mom,” the message said according to Hoa.
She said Tra My had gone to China and was planning to reach England via France.