Britain has sent documents to Vietnam to help identify some of the 39 people found dead in a truck near London, Hanoi said Monday, as fears mount that most of the dead were Vietnamese. The eight women and 31 men found Wednesday in a refrigerated container in Essex, southeast England, were originally identified as Chinese. But several Vietnamese families have come forward saying they fear their relatives are among the dead. Officials started collecting DNA samples from families in Nghe An and Ha Tinh, impoverished central provinces where most of the suspected victims came from. On Monday, Vietnam said Britain had sent documents to help with the complicated task of identifying the bodies, many who were believed to be carrying falsified passports. “The UK side has sent four sets of dossiers related to the Essex lorry deaths... for verification coordination,” Deputy Foreign Minister Bui Thanh Son said, according to a report on the government’s website. Vietnam’s foreign ministry is developing files on the suspected victims, the report said, after hair and blood samples were collected from several families. The Vietnamese embassy in London has assigned a permanent diplomat to help with the investigation, the largest murder probe in Britain since the 2005 London suicide bombings. British police have charged the driver of the truck, Maurice Robinson, with 39 counts of manslaughter and conspiracy to traffic people. The 25-year-old from Northern Ireland, who also faces charges of conspiracy to assist unlawful immigration and money laundering, is due to appear in court on Monday. The truck tragedy has plunged communities in central Vietnam into mourning, as families desperately wait for news from their missing relatives. Vietnamese media reported that as many as 24 of the victims could be Vietnamese, although officials have not confirmed the number. Central Vietnam has long been a source of illegal migration to Britain for people seeking better lives. Vietnamese migrants often work illegally in nail bars or cannabis farms, heavily indebted and vulnerable to exploitations.