A murder and human smuggling investigation into the deaths of 39 people crammed together in the back of a tractor-trailer from Bulgaria is spanning Europe as authorities try to piece together how the truck made it to an industrial park near London.
British police discovered the bodies early Wednesday morning inside a large cargo truck at the Waterglade Industrial Park in Grays, a town in Essex about 25 miles east of London.
The truck was registered in Bulgaria to a company owned by a woman from Ireland, Bulgarian authorities said. But they said they could not yet confirm that the truck had started its journey in Bulgaria.
It remained unclear what route the truck took before it ended up in Essex.
British Prime Minister Boris Johnson called it an “unimaginable tragedy and truly heartbreaking.”
It is one of Britain’s worst cases of human smuggling. In 2000, 58 Chinese illegal immigrants were found dead inside a truck they were trapped in for hours at the port city of Dover.
Wednesday’s grim discovery also recalled the deaths in 2015 of 71 immigrants from Syria, Iraq and Afghanistan found suffocated in the back of a refrigerated truck abandoned on an Austrian highway close to the Hungarian border.
In Britain, police said they arrested the truck’s 25-year-old driver who was from Northern Ireland. He was arrested on suspicion of murder and was in custody.
Police said they were alerted to the truck by an ambulance service at 1:40 a.m. Wednesday. Authorities said it appeared the dead included 38 adults and possibly one teenager.
Chief Superintendent Andrew Mariner called it “a tragic incident where a large number of people have lost their lives,” according to the Press Association, a British news agency.
Mariner said investigators were working to identify the victims. He said the truck entered the United Kingdom at the Holyhead port in Wales on Oct. 19.
Holyhead is a main port of entry for ferries from Ireland. It is likely that this smuggling operation chose to enter Holyhead because there are few checks for human smuggling there, experts said.
By comparison, authorities have a number of ways to check for human cargo at the ports of Dover and Calais, where human smuggling has been a persistent problem. In those ports, sniffer dogs, monitors and high-tech surveillance technology are in use to catch human cargo.
Richard Burnett, the head of the Road Haulage Association, told the Press Association that the truck appeared to have been a refrigerated unit.
The National Crime Agency said its specialists were working on the case and would “take action against any organized crime groups who might have played a role in causing these deaths.”
In May, the agency warned that the number of cargo trucks carrying people into Britain was increasing.
“To put 39 people into a locked metal container shows a contempt for human life that is evil,” lawmaker Jackie Doyle-Price, who represents the region, told Parliament.