Young children were put in "significant danger" after being smuggled into the UK in the back of lorries - and the ringleader of the gang remains on the run.
The youngsters were dumped in laybys and "desperate for food and water," an investigation by National Crime Agency (NCA) found.
A warrant has been issued for the arrest of Tarik Namik, aged 45, after he failed to attend court for a sentencing hearing.
NCA says Namik "headed up" the "large-scale" operation bringing Kurdish migrants into the UK hidden in the back of lorries.
Namik, who ran a car wash in Stockport, Greater Manchester, was jailed for eight years in his absence at Manchester Crown Court. Four others were also locked up at the hearing.
The NCA said the organised crime group became subject of an investigation in 2017. Namik, of Oldham, Greater Manchester, operated "a sophisticated, lucrative criminal enterprise" transporting migrants from Iraq and Iran and had connections with other people-smugglers overseas, added the NCA.
Working for him were Hajar Ahmed, 39, of Blackley, Manchester, and Soran Saliy, 32, from Stoke-on-Trent, Staffordshire, who the NCA said would help co-ordinate the UK leg of the operation.
Habil Gider, 54, also from Stoke-on-Trent, would act as an escort for some of the migrants once they were in the UK, while Hardi Alizada, 32, from Nottingham, travelled out to Europe to co-ordinate from there, reports the Manchester Evening News.
In a statement, the NCA said: "The gang operated a sophisticated and lucrative criminal enterprise, utilising complicit lorry drivers usually from Turkey.
"Recordings found on Namik's phone suggest that he may have been involved in the smuggling of at least 1,900 migrants from the Balkans into France or Germany during a 50-day period, charging around 1,800 euros (£1,500) per migrant. The group would then offer two separate means of getting to the UK, which would incur extra cost.
"The first, an 'escorted' facilitation, would see individual migrants collected by complicit lorry drivers in France or Belgium and hidden within their lorry, sometimes within the wind deflector above the cab, then met by an escort - usually taxi-driver Gider - once they had arrived into Dover, Kent. Gider would then take them on to their final destination."
The court heard Gider was caught red-handed in November 2017 after his car was stopped by the NCA driving north on the M26 in Kent. An Iraqi-Kurd woman was found sitting in the rear – she had just arrived in a lorry into Dover.
He had been in contact with Saliy throughout the day prior to his arrest, but both Saliy and Namik threw away phones they had been using.
The NCA said the other method was to conceal larger groups of migrants in the back of a lorry, also driven by a complicit haulier, to be released once the driver was safely through border controls.
An NCA spokesman added: "Once here the migrants would claim asylum. In one such event in September 2017 nine migrants were released from a Polish lorry in a layby in Skelmersdale, Lancashire. Their escape was witnessed by another driver.
"One of the migrants had just dialled 999 to beg for help. The group, which included five children, were desperate for food and water and were taken to hospital.
"Prior to the event both Namik and Ahmed were in contact with a Belgian-based people-smuggler called Dilman Jamal Ali, to arrange their movement. Ali was later convicted in Belgium for offences in connection with the incident."
The NCA said Namik's operation was dismantled in April 2018, when he, Ahmed and Saliy, were arrested by officers. All five pleaded guilty to helping asylum seekers to enter the UK contrary to section 25A of the Immigration Act 1971.
Ahmed was jailed for four years and nine months; Gider for four years, six months; Saliy for five years, four months and Alizada for 16 months.
NCA Branch Commander Richard Harrison said: "The NCA have dismantled a prolific and sophisticated crime group involved in Organised Immigration Crime.
"The criminal group sought to subvert the UK asylum system for their own financial gain, putting vulnerable migrants – including young children - at great risk by transporting them in the back of lorries or in concealments.
"This investigation demonstrates the NCA’s commitment to tackling Organised Immigration Crime, working with partners to relentlessly pursue those intent on smuggling vulnerable migrants into the UK.
"One of these men – Tarik Namik – failed to answer bail today and we are now working with partners to secure his immediate arrest. Anyone with information on Namik’s whereabouts should contact the charity Crimestoppers or the NCA directly on 0370 496 7622."
Mike Duffy, Specialist Prosecutor for the Crown Prosecution Service, said: “These criminals were involved in a large scale, highly professional, people-smuggling operation, which aimed to secure the unlawful entry of asylum seekers into the United Kingdom for profit.
"The criminal organisation took substantial sums of money from vulnerable migrants desperate for a new life, promising to assist them into the country. Namik played a leading role in the network and oversaw the movement of a large number of migrants, some of whom, including children, were put in significant danger when being transported concealed in the back of a lorry.
"We worked closely with the NCA to build a strong case resulting in their conviction, disrupting the dangerous, exploitative and illegal movement of people into the country for profit.
"The CPS will use the Proceeds of Crime Act to relentlessly pursue any ill-gotten gains from this offending."
