Those inside the container had suffocated, trying to scramble over each other in a forlorn hope of opening the door.

Just two of the human cargo were alive. They were unconscious, but had survived only because tiny amounts of air had become available with each death.

The mass fatalities, of 56 men and two women, were 19 years ago.

The dead were Chinese nationals who had been smuggled in to Dover through Europe.

The investigation which followed led to a web of criminal connections in China, Turkey, the Netherlands and Britain organised by a Chinese snakehead gang headed by a woman operating from Rotterdam.

39 bodies found in lorry container in Essex Show all 15 1 /15 39 bodies found in lorry container in Essex 39 bodies found in lorry container in Essex Thirty-nine bodies have been found in a lorry container in Essex, police have said PA 39 bodies found in lorry container in Essex The discovery of 38 adults and one teenager was made at an industrial estate in Thurrock Reuter TV 39 bodies found in lorry container in Essex Police said they believed the lorry had come from Bulgaria and entered the UK at Holyhead, in Wales, on Saturday. Getty 39 bodies found in lorry container in Essex Essex Police said it had launched a murder investigation after its officers were called to Waterglade Industrial Park, in Grays, in the early hours of Wednesday morning Reuter TV 39 bodies found in lorry container in Essex A 25-year-old-man from Northern Ireland has been arrested on suspicion of murder PA 39 bodies found in lorry container in Essex In a statement, Chief Superintendent Andrew Mariner said: “This is a tragic incident where a large number of people have lost their lives. Our enquiries are ongoing to establish what has happened. “We are in the process of identifying the victims, however I anticipate that this could be a lengthy process. Reuter TV 39 bodies found in lorry container in Essex THURROCK, ENGLAND - OCTOBER 23: Police stand near the site where 39 bodies were discovered in the back of a lorry on October 23, 2019 in Thurrock, England. The lorry was discovered early Wednesday morning in Waterglade Industrial Park on Eastern Avenue in the town of Grays. Authorities said they believed the lorry originated in Bulgaria and entered the country at Holyhead on October 19. The suspected driver was arrested in connection with the investigation. (Photo by Leon Neal/Getty Images) Leon Neal Getty 39 bodies found in lorry container in Essex THURROCK, ENGLAND - OCTOBER 23: A Police forensic investigation team are parked near the site where 39 bodies were discovered in the back of a lorry on October 23, 2019 in Thurrock, England. The lorry was discovered early Wednesday morning in Waterglade Industrial Park on Eastern Avenue in the town of Grays. Authorities said they believed the lorry originated in Bulgaria and entered the country at Holyhead on October 19. The suspected driver was arrested in connection with the investigation. (Photo by Leon Neal/Getty Images) Leon Neal Getty 39 bodies found in lorry container in Essex Police activity at the Waterglade Industrial Park in Grays, Essex, after 39 bodies were found inside a lorry container on the industrial estate. PA Photo. Picture date: Wednesday October 23, 2019. Early indications suggest there 38 are adults and one teenager, police said. The lorry is from Bulgaria and entered the country at Holyhead, North Wales, one of the main port for ferries from Ireland. See PA story POLICE Container. Photo credit should read: Stefan Rousseau/PA Wire Stefan Rousseau PA 39 bodies found in lorry container in Essex THURROCK, ENGLAND - OCTOBER 23: A Police forensic investigation team are parked near the site where 39 bodies were discovered in the back of a lorry on October 23, 2019 in Thurrock, England. The lorry was discovered early Wednesday morning in Waterglade Industrial Park on Eastern Avenue in the town of Grays. Authorities said they believed the lorry originated in Bulgaria and entered the country at Holyhead on October 19. The suspected driver was arrested in connection with the investigation. (Photo by Leon Neal/Getty Images) Leon Neal Getty 39 bodies found in lorry container in Essex Thurrock deaths: 39 bodies found in lorry container in Essex Reuter TV Reuter TV 39 bodies found in lorry container in Essex Police activity at the Waterglade Industrial Park in Grays, Essex, after 39 bodies were found inside a lorry container on the industrial estate. PA Photo. Picture date: Wednesday October 23, 2019. Early indications suggest there 38 are adults and one teenager, police said. The lorry is from Bulgaria and entered the country at Holyhead, North Wales, one of the main port for ferries from Ireland. See PA story POLICE Container. Photo credit should read: Aaron Chown/PA Wire Aaron Chown PA 39 bodies found in lorry container in Essex Police cordon at the road leading to the Waterglade Industrial Park in Grays, Essex, after 39 bodies were found inside a lorry container on the industrial estate. PA Photo. Picture date: Wednesday October 23, 2019. Early indications suggest there 38 are adults and one teenager, police said. The lorry is from Bulgaria and entered the country at Holyhead, North Wales, one of the main port for ferries from Ireland. See PA story POLICE Container. Photo credit should read: Stefan Rousseau/PA Wire Stefan Rousseau PA 39 bodies found in lorry container in Essex Police officers are seen at the scene where bodies were discovered in a lorry container, in Grays, Essex, Britain October 23, 2019. REUTERS/Hannah McKay HANNAH MCKAY Reuters 39 bodies found in lorry container in Essex Police officers are seen at the scene where bodies were discovered in a lorry container, in Grays, Essex, Britain October 23, 2019. REUTERS/Hannah McKay HANNAH MCKAY Reuters

Jing Ping Chen, known as Little Sister Ping, barely five feet tall, is believed to have been responsible for smuggling up to 175,000 people – earning over £12m in the process.

She was sentenced to three years in jail by a Dutch court in 2003 for her part in the plot. The Dutch lorry driver, Perry Wacker, received a jail sentence of 14 years for manslaughter at Maidstone Crown Court.

While reporting on the Dover deaths, The Independent found links between gangs engaged in trafficking in humans, drugs and guns in the Netherlands and Turkey.

British and Dutch investigators, meanwhile, revealed how these elements and accompanying laundering operations revealed contacts between organised crime and political extremists.

The investigation into the snakeheads was carried out by a number of different police forces.

In 2016, Theresa May announced the UK’s intelligence services would be pursuing human smugglers.

MI6 and GCHQ were to be given extra resources to go after networks abroad while MI5 was tasked to work with police to track down those who had been trafficked in the UK and the criminal elements who were controlling their lives.

The 39 people whose bodies were found in the lorry in Grays, Essex, on Wednesday were also, it has now emerged, Chinese nationals. The trade in humans, with gangs getting rich on their misery, continues two decades on.

The investigation is being carried out by Essex Police. Mo Robinson, the 25-year-old-lorry driver from Portadown in Northern Ireland, is under arrest.

The National Crime Agency (NCA) said it had sent officers to assist and “identify any organised crime groups which may have taken part”.

Security officials say that it is likely that such links would be found with organised crime and other agencies are then likely to get involved under Project Invigor, which was set up in 2017 and had gathered intelligence in eastern Europe, the Middle East, North Africa and the Sahel states.

Essex lorry deaths truck moved as investigation continues

Separately, Europol also has a centre collating information on people smuggling into the EU.

The UK government has insisted all efforts are being made to ensure cross-border cooperation on the issue will continue after Brexit, but officials acknowledge that the extent of that will depend on the terms under which the UK’s departure actually takes place.

It has been reported that Boris Johnson’s chief advisor, Dominic Cummings, had suggested that security ties will be cut with EU states which supported a delay on Brexit.

In a briefing to The Spectator, a “senior government source” said that backing another extension would be seen by the prime minister as a “hostile interference in domestic politics”.

The source said that countries supporting another delay would “go to the back of the queue” for future cooperation on everything from trade to security.

Former work and pensions secretary Amber Rudd yesterday named the source as Mr Johnson’s chief adviser Dominic Cummings – a claim that was not denied by No 10.

Smugglers have been trying different routes into the UK since the refugee camp at Calais was shut down and, according to law enforcement officials, attempts are expected to continue after tighter border controls are brought in after Brexit.

There are worries, they point out, about the adequacy of security measures. Two separate warnings were issued, by the NCA, and Border Force, about Purfleet in Essex becoming a destination for smugglers three years ago.

The primary focus of investigation will now be in Northern Ireland and Bulgaria.

In Sofia, Boyko Borisov, the prime minister, said the lorry in which the people died, had not been in Bulgaria since 2017.

“We are all affected by this mass death. Two more trucks are registered here. There is no way we can be connected except the truck sign. Nevertheless, we are working very well with the English services, so we will cooperate as much as possible,” he insisted.

Thurrock MP pays commends emergency services who attended scene of Essex lorry tragedy

A spokesman for the country’s foreign affairs ministry said the truck was registered in the country under the name of a company owned by an Irish citizen. He said it was “highly unlikely” that they were Bulgarian citizens.

Bulgaria, however, has become a hub for smuggling, including of people, to western Europe. The US State Department’s “Trafficking in Persons” report, published in June 2019, said government in Sofia does not meet the minimum of standards for elimination of trafficking, but are making efforts to do so.

The report was based on published CIA findings.

This stated: “Bulgaria is a source and, to a lesser extent, a transit and destination country for men, women, and children subjected to sex trafficking and forced labour; Bulgaria is one of the main sources of human trafficking in the EU; women and children are increasingly sex trafficked domestically, as well as in Europe, Russia, the Middle East, and the US; adults and children become forced labourers in agriculture, construction, and the service sector in Europe, Israel, and Zambia; Romanian girls are also subjected to sex trafficking in Bulgaria.

“Bulgaria does not fully comply with the minimum standards for the elimination of trafficking; however, it is making significant efforts to do so; in 2014, authorities prosecuted and convicted fewer traffickers and issued suspended sentences for the majority of those convicted; victim protection efforts declined and were minimal relative to the number of victims identified; funding for the state’s two NGO-operated shelters was significantly cut, forcing them to close; specialised services for child and adult male victims were non-existent; the government took action to combat trafficking-related complicity among public officials and police officers (2015).”