Britain’s strategy to tackle people smugglers sending migrants across the Mediterranean is doomed to fail, a new Cambridge University study has suggested.

Wiretapped telephone conversations between gangs show there are no “kingpins” who can be removed and that arrests only cause other groups to take control of the lucrative human market.

The study, entitled Out of Africa: The organisation of migrant smuggling across the Mediterranean, concluded that UK-supported sea operations to push refugee boats back to Libya will be ineffective.

The author, Dr Paolo Campana, said the crisis cannot be stopped without addressing the demand driven by conflict, instability and poverty in African countries.

“Criminal justice responses require the adoption of coordinated tactics involving all countries along the route to target these localised clusters of offenders simultaneously,” he warned.

”This is a market driven by exponential demand, and it is that demand which should be targeted.

“Land-based policies such as refugee resettlement schemes are politically difficult, but might ultimately prove more fruitful in stemming the smuggling tide than naval operations.”

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British forces have been training coastguard forces affiliated to the fragile Government of National Accord (GNA) to intercept dinghies launched from Libya, despite warnings that the operations violate international law by forcing refugees back to a country where they face torture and abuse.

The Independent revealed that some officials are taking bribes to free migrants from detention centres attempt the crossing again, with rape, forced labour and murder reported inside squalid prisons.

The UK and other European nations have been heavily criticised for failing to resettle refugees from Libya, despite their part in its continuing conflict, and instead bolstering sea operations aiming to stop the boats.

Dr Campana called for sea operations to be replaced with a wider set of policies to “reduce the demand for smuggling services”.

“The adoption of schemes that resettle refugees directly from conflict zones would be a step in this direction,” he added.

In July, the European Council extended its anti-smuggling naval operation until next December, with a mandate to disrupt migrant smugglers and human traffickers and training Libyan coastguard and navy forces.

Britain is among nations sending surveillance ships to the country’s coast to monitor “criminal gangs” deemed responsible for the refugee crisis, while Italian police have been arresting alleged traffickers rescued at sea.

But Dr Campana found that arresting any individual smuggler will only result in rivals immediately seizing their “market share”.

In pictures: A day of refugee rescues in the Mediterranean Sea Show all 7 1 /7 In pictures: A day of refugee rescues in the Mediterranean Sea In pictures: A day of refugee rescues in the Mediterranean Sea A baby being taken on to MSF's Bourbon Argos ship from a boat carrying 130 migrants and refugees Lizzie Dearden In pictures: A day of refugee rescues in the Mediterranean Sea A refugee boat carrying 101 people being rescued by MSF's Bourbon Argos Lizzie Dearden In pictures: A day of refugee rescues in the Mediterranean Sea A refugee boat carrying 101 people being rescued by MSF's Bourbon Argos all images by Lizzie Dearden In pictures: A day of refugee rescues in the Mediterranean Sea A baby among refugees on a boat carrying 185 people off the coast of Libya Lizzie Dearden In pictures: A day of refugee rescues in the Mediterranean Sea Migrants and refugees sleeping after being rescued by MSF's Bourbon Argos ship Lizzie Dearden In pictures: A day of refugee rescues in the Mediterranean Sea A crew from MSF's Bourbon Argos ship rescuing a boat carrying 130 migrants and refugees off the coast of Libya, at sunrise Lizzie Dearden In pictures: A day of refugee rescues in the Mediterranean Sea A woman in a stretcher being lifted onto MSF's Bourbon Argos ship from a boat carrying 130 migrants and refugees off the coast of Libya Lizzie Dearden

“The smuggling ring moving migrants from the Horn of Africa to Northern Europe via Libya does not appear to have the thread of any single organisation running through it,” he said.

“This is a far cry from how mafia-like organisations operate, and a major departure from media reports claiming that shadowy kingpins monopolise certain routes.”

Widespread conflict and lawlessness since the UK-backed ousting of dictator Muammar Gaddafi in 2011 and the ensuing civil war have led to a thriving human trade culminating in open-air slave markets.

Libyan gangs have linked up with groups in Niger, Chad and Sudan to the south to create trafficking networks stretching across Africa.

Dr Campana’s study found that on the other side of the Mediterranean, they also extended to the UK, Germany, Scandinavia and countries including Israel, Canada and Turkey.

“People specialise,” he explained. “There was a clear separation between those providing smuggling services, those kidnapping for ransom, and those, like the militias, ‘governing’ spaces and supplying protection.”

Dr Campana, of Cambridge University's Institute of Criminology, conducted the research using evidence from an 18-month investigation by Italian prosecutors following a shipwreck that killed 366 people off the coast of Lampedusa in 2013.

It included data from wiretapped telephone conversations between smugglers at all stages, migrants’ testimonies and interviews with police.

In May Libyan coastguard were accused of opening fire on a boat of refugees (Jugend Rettet)

The research, published in the European Journal of Criminology, found that each stage of transnational migration routes via Libya had “independent and autonomous” smugglers, militias and kidnappers competing over vulnerable migrants.

Of the 292-strong network linked to the Lampedusa disaster – the majority were active in and around Tripoli, followed by the Libyan desert, Sicily, Italy, the Horn of Africa and Nordic countries.

Dr Campana said there was a loose hierarchy between “organisers” who give orders to “aides” who make up the bulk of smuggling groups.

Wiretaps and testimonies suggest that migrants have to pay separate vendors for each leg of the journey, frequently using the informal money transfer system of Hawala.

One couple were charged $3,600 (£2,600) for a couple to cross the Mediterranean, while another recorded smuggler demanded €150 (£130) per person for a car trip from Sicily to Rome.

Migrants interviewed by The Independent have described being conned by armed gangs, paying one smuggler for the whole journey to European shores only to find themselves charged again by a different group along the route.

Those unable to pay are frequently imprisoned and ordered to contact loved ones for more money, sometimes while being tortured or sexually abused, or forced into unpaid labour or prostitution to cover the supposed debt.

Sub-Saharan migrants sit at the Qanfouda detention centre, in the southern outskitrs of Benghazi (Getty)

Many of those reaching Italy did not intend to come to Europe but hoped to live and work in Libya, only to find themselves kidnapped and forced on dinghies across the Mediterranean.

According to the UN estimates, there are between 700,000 and 1 million migrants in Libya; more than 2,300 have crossed from the country to Italy so far this year.

The UN announced plans to fly 15,000 migrants to their home countries – mostly in sub-Saharan Africa – from detention centres in Libya last month as part of a voluntary programme.

But flights were suspended after deadly clashes between the GNA’s Special Deterrence Force and an armed group closed the only functioning airport in Tripoli and damaged passenger jets earlier this month.

The treacherous passage across the Central Mediterranean has become the deadliest sea crossing in the world since the start of the refugee crisis, claiming almost 200 lives so far this year after around 3,000 men, women and children died in 2017.