Iraqi-born Shwana Rafiq put the lives of entire families at risk by hiding them in trailers heading for Britain where temperatures never got above 40F (4C).
The 36-year-old was sentenced after he admitted playing a lead role in an international criminal gang which organised a 'large number' of operations involving the smuggling of Kurds.
Spanish police believe Shwana's gang were responsible for smuggling more than 100 people into the UK between 2017 and 2018, earning up to £850,000.
Shwana's modus operandi echoed some of the deadly tactics used by the people smugglers blamed for the deaths of 39 Vietnamese migrants found dead in a refrigerated truck in Essex last month.
He was jailed after striking a pre-trial plea bargain deal with prosecutors at a court in Teruel east of Madrid.
State prosecutors had initially been seeking a 14-year prison term for Spanish expat Shwana on charges of money laundering and people trafficking before he received a reduced sentence as part of a guilty plea.
His Spanish wife Esperanza Martinez, who was facing a prison sentence of up to 12 years before she admitted to being his accomplice, was handed a two-year jail term for human trafficking which will be suspended as she is a first-time offender.
Five other people linked to the people smuggling organisation were given prison sentences ranging from six months to a year set to be suspended at a later date because they all have clean records in Spain.
They included a 39-year-old Iranian with a British passport identified as Rabeen Mohamad who was extradited to Spain from Switzerland to face trial. He was also convicted of a crime of human trafficking.
The police operation which resulted in the court convictions, outlined in a 30-page sentencing document released Tuesday in the wake of the plea agreements, was sparked by the discovery of six Iraqis in the back of a lorry in France in 2017.
The Iraqis, who were discovered in a UK-bound refrigerated lorry at a service station in near Teruel, central Spain, were members of the same family. Four were children.
They alerted the unsuspecting lorry driver to their plight by screaming for help hours after being hidden in the trailer by Shwana when he broke into it and then locked it back up with them inside.
The following month eight Turkish and Iraqi migrants including four children were discovered in almost identical circumstances in a second UK-bound lorry near the same spot.
Spanish police said after father-of-three Rafiq's arrest in January 2018 they believed the human trafficking gang he led had smuggled more than 100 people into Britain over the previous 12 months.
Describing the organisation's methods, a Spanish National Police spokesman said: 'It consisted of the introduction of groups of between six and eight people, generally families with young children including babies just months old, in the back of refrigerated trucks bound for the UK.
'The normal length of stay would be between 30 and 40 hours at temperatures of no more than four degrees Celsius.
'The gang was conscious of the risks these sorts of journeys entailed, and they acted with complete disdain for the lives and wellbeing of the people they were trying to smuggle into Britain.
'At times they even resorted to hitting those who had panic attacks while they were travelling or giving them drugs to calm them down.
'The price people were charged increased considerably if they requested the presence of a smuggler inside the back of the lorry to help them.'
Footage released by Spanish police showed an army of heavily-armed officers outside one of the properties they raided while one shouted out: 'Open the door, we're the police, open up or we'll break it down.' and yelling 'Get on the ground' as they raced in.
Rafiq, handed a six-month prison sentence in France after being caught trying to smuggle two Kurdish migrants into the UK in the boot of a rental camper van in September 2017, had the help of relatives based in Britain according to the judges who jailed him.
It is not clear if they too have been arrested following the crackdown in Spain.
Lead judge Fermin Hernandez Gironella said: 'Their role would be to receive the migrants when they reached the UK and to send the money relating to the payment by the migrants for the trips they had made.'
The three sentencing judges added: 'Given the low temperatures they travelled in, which were never above four degrees Celsius, there was a clear risk to their life and physical integrity, to the point that in some cases the migrants themselves had to raise the alarm so they could be rescued.
'The organisation has organised and participated in a large number of illegal transfers of migrants and the financial benefits they have obtained would have been high.
'The activities carried out by the criminal gang consisted of transferring unauthorised migrants to different countries in Europe but in the case of this organisation especially, to the United Kingdom.'
None of the migrants who paid to get to Britain took their own legal action against the human trafficking gang and many are suspected to have reached the UK after vanishing from Spain.
Shwana was recorded bragging to one migrant who wanted to make the trip: 'There's not a week I don't send families.'
He told an accomplice in another taped phone call he had resolved a 'situation of crisis' with another migrant he was trying to smuggle to the UK by 'hitting him.'
The judges concluded in their sentencing document: 'Schwana carries out leadership functions within the organisation, which involve directing and organising the pick-up of the migrants and sorting out their temporary stays in Spain and their clandestine transfer to the UK.
'The organisation is fully aware of the risks these sorts of journeys in the backs of refrigerated lorries entail.
'Schwana was recorded saying the time migrants would have to spend in a lorry averaged between 30 and 40 hours.
'The phone conversations that were taped showed the UK was the most popular destination with Kurdish migrants followed by Ireland.'
One of the lorries Schwana targeted belonged to El Mosca, the Spanish haulage firm whose driver was questioned by Kent police after five migrants were filmed leaving a HGV on the M25 near Dartford in October 2016.
Investigators in both countries concluded the truckers were victims of people smugglers and had no idea their vehicles had been broken into.
The bodies of 39 Vietnamese migrants were found in a lorry trailer in an industrial park in Grays, Essex, in the early hours of October 23.
Police confirmed earlier this month they included ten teenagers, the youngest of them being two 15-year-old boys.
The lorry driver, 25-year-old Maurice Robinson, has been charged with a string of offences including 39 counts of manslaughter.
Eamon Harrison, 22, from Mayobridge, Co Down, faces extradition to the UK after allegedly delivering the trailer the migrants were found in to the Belgian port of Zeebrugge before its onward journey to Britain.
Ronan Hughes and his younger brother Christopher, both from Co Armagh, are being sought by police on suspicion of manslaughter and human trafficking.
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