The 48-year-old man from Northern Ireland was arrested at Stansted Airport, Essex, on October 25 on suspicion of trafficking and manslaughter.

Police earlier arrested three people, including driver Mo Robinson, 25, who drove a 39-body container on October 23, with husband and wife Thomas and Joanna Maher, both 38. Bulgarian television reported that the Maher couple owned the Scania tractor that Robinson controlled. However, the two told reporters they sold it 13 months ago to a company in Monaghan County, near where Robinson lives.

Robinson discovered 39 bodies when opening a frozen container on October 23 at Waterglade Industrial Park, Grays, Essex. The driver called an ambulance, then the medical staff informed the local police.

The Essex County Police of England initially believed that all the victims, including 31 men and 8 women, were Chinese, but authorities were investigating suspected victims of non-Chinese citizenship. The representative of the Vietnamese Embassy in the UK said he was working closely with the police to find out information related to this new development.

Eleven of 39 bodies were taken to Broomfield Hospital in the town of Chelmsford, Essex, on the evening of October 24 for an autopsy. The remaining bodies are expected to be completed by the end of the week.