(AP) — UK police in Essex say all of the 39 victims found dead in a truck container in southeastern England are now out of the truck and in a mortuary awaiting autopsies.

But Detective Chief Inspector Martin Pasmore says the victims have not been identified and very few documents were found with the bodies. He met Saturday with the Vietnamese ambassador amid reports on social media that many of the victims were from that south-east Asian country.

Pasmore again appealed to those who might have information on the victims to help with inquiries.

Four people have been arrested so far in the case, one of Britain’s deadliest smuggling disasters.

Analysis: Migrants Who Died in Lorry are Victims of Weak Borders and Callous People-Smugglers https://t.co/tHfYhikx5c — Breitbart London (@BreitbartLondon) October 24, 2019

Vietnamese families are mourning lost children and desperately seeking information about the 39 people who died in the back of a sealed truck in southeastern England this week, even as British officials struggle to identify victims whose identities were obscured by the people smugglers who led them to their deaths.

Police in Britain are questioning four people in connection with the tragedy as they grappled with one of the deadliest cases of trafficking ever reported in the country. In an effort to treat the victims with respect and preserve evidence, authorities are slowly transferring the bodies from the truck to a hospital mortuary where the process of identification will take place.

But the task is likely to be difficult. People smugglers normally take the passports of their passengers to obscure their identities, stripping them of their names and giving them new documents when they arrive at their destinations.

Police initially believed the victims were Chinese but later acknowledged that the details were still evolving. Attention shifted to Vietnam after the family of a 26-year-old Vietnamese woman released text messages suggesting she had suffocated in the truck.

‘The majority of the Chinese trafficking victims I work with have accrued debts to Snakehead gangs’ @shalinipatel0 Post-mortem examinations are due to be carried out on some of the 39 people found dead in a lorry in Essex.https://t.co/OvUEwY8IXp pic.twitter.com/86P1S3W5fV — Victoria Derbyshire (@VictoriaLIVE) October 25, 2019