British police investigating the discovery of 39 bodies in a truck said Friday they had arrested two people on suspicion of manslaughter and conspiracy to traffic people.
Eight women and 31 men, believed to be Chinese nationals, were found in the refrigerated trailer on Wednesday, in a case that has shocked Britain.
After detaining a 25-year-old truck driver from Northern Ireland at the scene on suspicion of murder, Essex police confirmed two additional arrests on Friday. A man and a woman, both aged 38 and from Warrington in Cheshire, northwest England, "have been arrested on suspicion of conspiracy to traffic people and on suspicion of 39 counts of manslaughter", the force said.
The first autopsies were to take place Friday as investigators attempt to establish how they died before the work begins on trying to identify the victims. Ambulances had been called to a parked-up truck in an industrial zone in Grays, east of London, early Wednesday but all the victims inside were already dead.
The refrigerated trailer had arrived at nearby Purfleet on the River Thames estuary on a ferry from the Belgian port of Zeebrugge just over an hour before ambulance crews called the police at 1:40 am. The truck which collected the trailer had left the port 35 minutes before that call.
The first 11 corpses were recovered from the trailer on Thursday and taken to a nearby hospital mortuary. Autopsies will attempt to establish how the victims died.
"Formal identification will then follow... and will be a lengthy but crucial part of this investigation. As our investigations continue, the picture may change regarding identification," the police said Friday.
Detectives have also searched three addresses in Northern Ireland. The police investigation is Britain's largest murder probe since the 2005 London suicide bombings. Prime Minister Boris Johnson described Wednesday's discovery as an "unimaginable tragedy".
Questions have been raised about when the victims entered the refrigerated trailer, where temperatures can be as low as minus 25 degrees Celsius (minus 13 degrees Fahrenheit).
The crossing to Purfleet from Zeebrugge, one of the world's busiest ports for cargo on trucks, takes nine to 12 hours.
Belgian investigators were working to establish where the trailer came from before reaching the port.
"We have ways to reconstruct the route of the container but it's not instantaneous, it can take time," Eric Van Duyse, spokesman for the Belgian federal prosecutor's office, told AFP.
People living close to the port at Purfleet said illegal immigrants were a familiar sight.
"It's a magnet for illegals," said Janet Lilley, 61.
"People would come strolling out of the docks, get in the vans and that's it, they drive off." Lee Tubby, 45, who lives opposite the port, said he has seen people "climbing out the top and out the back" of trucks and cutting the plastic roof covering to climb through.
"We've had people just come out of the port knocking on the door asking for shoes, asking for water," he said.
Meanwhile, Beijing-based political analyst Hua Po said the flow of Chinese workers to Europe has gone up as "China's own policy has become more and more conservative and closed" under President Xi Jinping.
"The survival of private enterprises is becoming more and more difficult, resulting in an increase in the number of unemployed people," Hua told AFP.