LONDON - British police arrested a man and a woman Friday in connection with the deaths of 39 people in a truck container in southeastern England.
In a statement, police in Essex county said they have arrested two people, both 38, from Warrington, England, "on suspicion of conspiracy to traffic people and on suspicion of 39 counts of manslaughter."
They also said they have asked for extra time to question the 25-year-old driver of the refrigerated truck, who has been arrested on suspicion of murder.
In the early hours of Wednesday, British police, tipped off by local ambulance services, were called to an industrial estate about 25 miles east of central London in the town of Grays, where they discovered 39 bodies. The police said the victims are believed to be Chinese nationals.
The gruesome discovery has turned into one of Britain's largest homicide cases, with investigations extending to Belgium, Ireland, Bulgaria and China.
Chinese Foreign Ministry spokeswoman Hua Chunying told reporters at a daily briefing Friday that Chinese officials have arrived on the scene in Essex but could not yet confirm the nationalities or identities of the dead migrants.
British investigators are working to determine the identities of the victims, how they died and the possible smuggling gangs involved. Post-mortem examinations of 11 of the deceased were due to start on Friday afternoon.
Experts who follow human trafficking trends suggested that the Essex victims could have been compelled into forced labor. Or they could have been migrants who paid their way for the dangerous journey gone horribly wrong.
Britain's National Crime Agency said it was working to identify "organized crime groups that may have played a part."
The bodies of the 39 people - eight women and 31 men - were found at Waterglade Industrial Park in Grays, a town on the north bank of the River Thames.
Essex Police and Belgian prosecutors said the refrigerated container arrived by sea from Zeebrugge, a Belgian port, and docked at Purfleet, a small port in Essex on the Thames, shortly after 12:30 a.m. Wednesday.
Police said the truck that picked up the container at Purfleet entered Britain separately, via ferry from Dublin, at Holyhead port in North Wales on Sunday.
New GPS tracking data shows that the refrigerated container crossed the English Channel several times over the past week.
The case echoed a fatal episode in June 2000, when the bodies of 58 Chinese migrants were found in a shipping container in the English port city of Dover. Those victims were supposedly destined to work in Britain as domestic servants, authorities said. The following year, a Dutch driver was sentenced to 14 years in jail for manslaughter. The immigrants, who paid a smuggling gang $26,000, suffocated after the driver closed a vent on the truck during a five-hour ferry ride across the English Channel.
In February 2004, at least 21 Chinese migrants who were picking cockles on the coast in the dark were caught in treacherous tides and drowned. The event, in Morecambe Bay in northwestern England, focused attention on illegal forced laborers smuggled into Britain.
Lucy Moreton of the Immigration Services Union, which represents British border, customs and immigration officers, said that desperate attempts to reach Britain appear to be on the rise. She described a form of modern-day slavery in which Chinese, Bangladeshi, Vietnamese and others allow themselves to be shipped to Britain, where they toil for years in construction, domestic service, agriculture, nail salons and the sex trade to "pay back" the debt they owe gangs for smuggling them abroad.
Richard Burnett, chief executive of the Road Haulage Association, said there are not enough security checks in many European ports and that this could be exacerbated with Brexit, as the United Kingdom's looming departure from the European Union is known.
"We've found it hard enough to try and get the Europeans to accept that this is a collective problem," he said. "There are no incentives for the Europeans to really help us if we're exiting the E.U. Their view is that this is our problem because these people want to get to the U.K."
Police have not named the driver, although several British media outlets have identified him, citing sources in Northern Ireland, and posted photos from what were said to be his social media accounts. Several of his friends have defended him. Some suggested that he could have been the one who called the ambulance services.
"We have not speculated about the identity of this man, and we will not do so," Essex police said in a statement Thursday.
The truck was registered in Varna, Bulgaria - a port city on the Black Sea - to a company owned by an Irish citizen, according to the Bulgarian Foreign Ministry. Bulgarian Prime Minister Boyko Borissov told a local television broadcaster that the truck left immediately after it was registered in 2017 and had not returned.
British officials had issued warnings about the route the container took across the North Sea.
In 2016, Britain's Border Force identified Zeebrugge, along with the Hook of Holland, as key ports for "clandestine arrivals" into Britain.
In a report published last year, Britain's National Crime Agency said Belgium had "become a location of greater focus" for human trafficking and that smuggling activity increased following the closure of a migrant camp in Dunkirk, France.
Analysts said Zeebrugge lacks many of the security measures - including sniffer dogs and high-tech monitors - employed in French ports.