LONDON, UNITED KINGDOM -- A British judge on Friday handed down sentences of 27 and 20 years to the ringleaders of a people smuggling plot that led to the death of 39 Vietnamese migrants in horrific conditions in the back of a lorry.

The 39 -- the youngest of whom were two 15-year-old boys -- suffocated in the container as they were being transported to what they had hoped would be new lives in Britain.

The lifeless bodies of the migrants were discovered inside the sealed unit at a port near London in October, 2019.

The case cast a shocking new light on the lengths migrants will go to to reach Britain -- and the gangs exploiting their desperation.

Ringleaders Ronan Hughes and Gheorghe Nica, who were convicted on 39 counts of manslaughter, were jailed at London's Old Bailey criminal court for 20 years and 27 years respectively.

Truck drivers Maurice Robinson and Eamonn Harrison were also given 13-year and 18-year sentences respectively.

Judge Nigel Sweeney told the court that the gang's operation was a "sophisticated, long running and profitable one to smuggle mainly Vietnamese migrants across the channel".

He told the defendants they would serve at least two-thirds of their terms in custody, instead of the usual half.

Robinson, from Craigavon, Northern Ireland, found the bodies in the container after picking it up following its cross-Channel journey.

He pleaded guilty to 39 manslaughter charges, as did haulage boss Ronan Hughes, 41, from Armagh, also Northern Ireland.

Harrison, of County Down, Northern Ireland, and Romanian national Nica, from Basildon, east of London, denied manslaughter but were found guilty after a 10-week trial that ended last year.

Harrison claimed during the trial he did not know the migrants had been loaded into the lorry he drove to Zeebrugge in Belgium, where he caught the ferry to Britain.

'SHOCKED'

Detective Chief Inspector Danny Stoten, of Essex Police, said outside court that the gang "made their money from misery".

"They treated the victims as a commodity and they transported them in ways that we would not transport animals," he said, adding he hoped the case sent a strong message that others involved in this activity "will face justice".

The group of migrants endured scorching temperatures inside the container.

Haulage firm boss Hughes, 41, closed his eyes during the trial as he heard recordings of the victims' distressing final moments.

In one message, a man struggled for air as he apologised to his family, saying "I can't breathe".

"I want to come back to my family. Have a good life," he added, as distressed noises from other victims were heard in the background.

The victims' families spelled out the human and financial cost of the tragedy in statements read out by prosecutor Jonathan Polnay in court.

Nguyen Huy Tung, whose 15-year-old son Nguyen Huy Hung died in the tragedy, said the family "did not believe it was the truth until we saw his body by our own eyes" at the hospital.

"We were very shocked, trembled, we lost track and awareness of our surroundings," he added. "My wife had fainted many times whenever our son's name was mentioned."

A forensic expert calculated it would have taken about nine hours for the air to turn toxic in the trailer, with death coming soon after.

Prosecutors have said the trapped migrants were unable to get a phone signal inside the container, whose cooling system was turned off.

Christopher Kennedy, 24, also from Armagh, and Valentin Calota, 38, from Birmingham, were also convicted for their part in the smuggling operation.