"This is a beautiful place. Or at least, it was a beautiful place."

Vincenzo Schiavone stands on the shoreline of Castel Volturno, gesturing over sparkling Mediterranean waters to the resort towns of the Amalfi coast. Just offshore are the islands of Procida and Vivara, and then Ischia: "Very beautiful … the thermal spas, the gardens, the lushness."

The contrast with Castel Volturno could not be more stark. Just metres away are open sewers where mangy dogs poke at rancid piles of garbage strewn across the main street. Along the coast, 12,000 waterfront homes are crumbling into the sea. Broken slabs of concrete are piled up on the sand, their tangled steel reinforcement protruding like rusty bones.

A dilapidated home crumbling into the sea at Castel Volturno, Italy. ( Foreign Correspondent: Louie Eroglu )

Castel Volturno, on the ancient coastal road between Rome and Naples, was once a seaside playground for the southern Italian elite. Now it is a lawless wasteland abandoned by the state.

According to Italy's anti-mafia agency, it is the European headquarters of the Nigerian mafia.

The seaside village's plunge into chaos has allowed this new mafia to take root amid the decay. Having disguised themselves among the migrants and refugees crowding boats from Libya, Nigerian crime lords have carved out a lucrative trade in people smuggling, drug running and prostitution. Even the local mafia fear them.

'An African city in Europe'

Vincenzo Schiavone says the Italian government has abandoned Castel Volturno. ( Foreign Correspondent: Louie Eroglu )

Flanked by his state-appointed police escorts, Mr Schiavone is clear about who is to blame for Castel Volturno's dire state: the Camorra, one of Italy's old mafia clans with its power base in nearby Naples.

"They were the beginning of the deterioration," he says. "For this, you have to give them credit."

In the 1970s, he moved here with his wife as a young surgeon, drawn to the beauty of what was then a beachside paradise. Mr Schiavone now owns the local hospital and is spending $130 million upgrading the site. When the Camorra found out, they wanted a cut.

The last time he refused their demands, they blew up his garage with his car inside it. For the last 12 years he has lived under constant police guard, fearing the vengeance of the Camorra.

Castel Volturno's population is now 50 per cent African, with a high proportion lacking legal status. ( Foreign Correspondent: Louie Eroglu )

Until the 1960s, Castel Volturno was known mostly for its tomatoes and buffalo mozzarella. Then the Camorra put it on the map for all the wrong reasons. Almost overnight, the mafia razed a coastal pine forest along the water's edge and built an 800,000-square-metre development without official authorisation.

Prosecutors eventually seized thousands of illegal homes and members of the Camorra went to jail for breaching planning and environmental laws.

For a time the buildings were left standing, unoccupied and increasingly decrepit. Then, in 1980, an earthquake outside Naples left 250,000 people homeless. The government bussed them to Castel Volturno to live in the vacant homes.

Authorities in Naples once had big plans for Castel Volturno. Today it is more like a war zone. ( Foreign Correspondent: Louie Eroglu )

Many local residents fled and when the earthquake victims eventually left too, the state chose not to invest in the rehabilitation of Castel Volturno. The illegal buildings were knocked down and, shockingly, the organised crime family behind the original, illegal development was awarded the contract to rebuild.

Today, the town stands as a testament to perpetual neglect. Real estate windows spruik absolute beachfront properties for less than 15,000 euros ($27,000).

"You can't tell people a place like this exists in Italy," says Roberto Saviano. "No-one would believe it … a whole city that's been constructed illegally."

The Camorra constructed an illegal residential development on the beachfront. ( Foreign Correspondent: Louie Eroglu )

Mr Saviano has been studying the changes in Castel Volturno with the same forensic obsession that saw him forced into hiding in 2007 after the publication of his global bestseller, Gomorrah. He's one of 20 Italian writers who are now under 24-hour police guard thanks to their mafia exposes.

The Nigerian mafia has come to Italy with a speed and force that's stunned even local mafia bosses, he says. Castel Volturno, where Mr Saviano once holidayed as a child, is now "an African city in Europe … culturally African". Half of the 50,000 residents are African, many of them undocumented. They find a place to hide here, but without official documentation or rights, many are easy prey for ruthless Nigerian mafia bosses.

"They immediately risk falling into the mobster net," he says. "The crime boss maybe says, 'If you don't have a house, I'll give you one for a little favour'. Then it's something more, something more."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 2 minutes 57 seconds 2 m 57 s Roberto Saviano talks about having a price on his head. ( Foreign Correspondent: Louie Eroglu )

This nominally remains a Camorra territory, but the old mob has learnt it pays to work with the Nigerians.

In 2008, the Camorra waged a bloody turf war on their upstart rivals, killing six Africans in a hail of bullets. After that showdown, they struck a truce. The Nigerian mafia is allowed to ply its illicit trade with the Camorra's permission while giving them a cut of the takings.

The Italian mafia went on a killing spree against Nigerians on the streets of Castel Volturno in 2008. Scars from the 122 bullets fired during the violence are still evident. ( Foreign Correspondent: Louie Eroglu )

"That area was handed over by the Italian networks to the Nigerians to manage," says Mr Saviano. "It was an admission first and foremost that it was no longer useful for the Camorra Casalesi clan to command street to street in Castel Volturno, because there's an enormous African community that could be better managed by the Nigerian mafia."

It's an arrangement the Nigerian mafia have worked out with the homegrown mob in other parts of Italy too.

A 2017 investigation published by the Cambridge Centre for Applied Research into human trafficking reported a faction of the Nigerian mafia, known as Black Axe, had "negotiated a deal with Cosa Nostra bosses in Sicily, buying the rights to operate in designated areas on the island".

Drugs, prostitution and people smuggling are among the illicit trades the Nigerian mafia now control. ( Foreign Correspondent: Francesco Bellina )

Vincenzo Schiavone has witnessed the gruesome effects of the Nigerian mafia presence in Castel Volturno in the emergency ward of his hospital, the Pineta Grande.

"We have seen people come in with heads struck with machetes, others have been bitten," Mr Schiavone says.

"They are terrible. They are effectively very violent. It's a kind of primordial violence."

The Pineta Grande also sees more drug mules than any other hospital in Italy. Doctors told Foreign Correspondent young African men are arriving with stomachs full of narcotics, some smuggling up to 1.2kg of cocaine in individually wrapped capsules the doctors describe as "eggs".

In other parts of Italy, authorities have noticed a rise in the number of young pregnant Nigerian women dying from drug overdoses when capsules burst inside them. Pregnant women are less likely to face suspicion in transit. No one would imagine they could be drug mules.

'I was in the hands of the mafia'

Women trafficked from Nigeria are often forced into prostitution to pay off a debt imposed by mafia people smugglers. ( Foreign Correspondent: Louie Eroglu )

On the Via Domiziana about 35km north of Naples, cars slow down to a crawl. This is one of southern Italy's major highways, ferrying commuters to the region's capital and beyond. This section of the road passing through Castel Volturno is well known to Italian men. Here they can buy sex from Nigerian girls — some as young as 12— for $8. Until two years ago, Joy Ezekiel was one of the women working on the Via Domiziana.

"Whenever a car came, they take us to the bush," says Joy, recalling the 12 months she spent as a prostitute. "I don't know who I'm going with. I don't know who this person is. What does he have for me? Is he going to beat me up?

"Sometimes they'll come, they'll show you a gun. They won't pay. They'll do what they want to do then leave."

The UN's International Organisation for Migration estimates 80 per cent of the Nigerian women and girls arriving by sea are likely to be victims of trafficking for sexual exploitation in Italy.

Joy Ezekiel was trafficked to Italy and forced to work as a prostitute. ( Foreign Correspondent: Louie Eroglu )

"I was actually in the hands of the mafia," says Joy. "The Nigerian mafia."

Joy looks uncomfortable as she tells of the harrowing circumstances which led her to Italy in 2016, at the height of Europe's migrant crisis. How she was tricked and traded by her own family, handed to the Nigerian mafia's people smugglers and trafficked 4,000km from her home in Benin City, Nigeria. In Italy, things would only get worse.

After the death of Joy's father, her home was regularly visited by a Pentecostal pastor who brought money for the family's single mother and six children. The pastor, a woman, eventually offered Joy a ticket to Italy with the promise of a job as a hairdresser and a room in her own mother's home.

The ruse was sealed with a black magic ceremony, known in Nigeria as "Ju Ju". Joy's forehead was marked with the blood of a slaughtered chicken and she was forced to swear an oath not to misbehave for her hosts in Italy. The consequences of breaking the curse, she believed, would be death to herself or her family in Nigeria.

Joy Ezekiel before she was trafficked to Italy by the Nigerian mafia. ( Supplied )

Leaving her home in a minibus, Joy still had no inkling that she was in the clutches of the mafia until she reached Agadez, Niger, where she was ordered to board one of several trucks packed with other migrants.

When armed men circled the convoy and demanded 500 euros from her driver, Joy's dreams of la dolce vita instantly began to sour. The driver, unable or unwilling to hand over the cash, offered up one of Joy's fellow passengers in lieu of payment. Joy has had nightmares about what might have happened to her.

Over two soul-destroying weeks, she watched one of her companions perish after two days without water in the searing desert heat. All of them facing dehydration. The remaining passengers were forced to drink from a well whose murky water could not hide the decomposing corpse inside. In a detention camp in Tripoli, her final stop before passage by boat across the Mediterranean, Joy saw a 13-year-old female companion taken captive and raped by seven men on rotation for an entire night.

Joy's mother (left) was left to look after her six children after their father died. ( Supplied )

When she finally arrived in Castel Volturno four months later, Joy was pregnant from rape. Despite everything, she still believed her pastor's mother might provide protection and her waking nightmare might soon be over.

She was wrong. The woman swiftly organised a home abortion and, still bleeding and traumatised, Joy was forced onto the Via Domiziana the same day.

Stripped of her identity and dignity, Joy was told the price of her freedom was 35,000 euros ($60,000). It would have taken Joy years to pay off her madam, had she not managed to escape.

Joy's experience of becoming entangled in the mafia's web is a common one. Blessing Okoedion told Foreign Correspondent how she was also enchanted by a trusted woman in her hometown in Nigeria.

When she arrived in Italy with a two-year working visa stamped in her passport, her madam took her documents and demanded 65,000 euros to get them back.

In the Nigerian underworld, it's women who are in charge, says Roberto Saviano. 'Men ... are their foot soldiers'. ( Foreign Correspondent: Francesco Bellina )

"I was also told to pay 150 euros a month to the Camorra," says Blessing. "I believe they have a collaboration. It's an agreement they have struck to work together."

Roberto Saviano says the Nigerian criminal network is organised and sophisticated. What makes it distinct in Italy is the place of women in its organisational structure.

"Prostitution, which is fundamental to the [Nigerian] mafia operations, is managed and run by the women," he says.

"At the heart of the Nigerian underworld, the people in charge are the women. They also command the men, who are their foot soldiers."

Joy and Blessing have both been granted Italian residency since reporting their stories to the police. Joy's captors are facing trial, but the legal system is so far struggling to prove the Nigerians are in fact mafia.

'We don't have the tools to combat them'

Law enforcement tactics used against Italy's homegrown mob are less effective against Nigerian organised crime, where language and culture barriers make infiltration harder. ( Foreign Correspondent: Francesco Bellina )

Palermo, on the island of Sicily, is the birthplace of the Italian mafia and the second major hub for Nigerian organised crime in Italy.

The Nigerians are the first foreigners to be prosecuted under Italy's anti-mafia laws. In 2007, 20 Nigerian men were convicted in Turin for crimes dating back to 1999.

In 2016, 17 Nigerian men were arrested in Palermo and charged with being members of the mafia. Five of them have since been acquitted. All were taken into custody on the testimony of a single informant.

The lawyer defending the men, Cinizia Pecoraro, says the whole trial is a sham and that Black Axe is at best a cult. She questions the existence of a Nigerian mafia in Palermo.

"No one in Palermo has been able to explain the group's configuration and what illegal activity it's involved in," she says. "Not even the informant. In all his questioning he never once referred to Black Axe being engaged in any illegal activity."

Men accused of being members of the Nigerian mafia face court in Palermo. ( Foreign Correspondent: Louie Eroglu )

Among those acquitted was the man Italy's anti-mafia intelligence agency, the DIA, called the Nigerian mafia's "Minister of Defence" in Italy.

When Foreign Correspondent spoke with the so-called minister, he denied ever having heard of Black Axe.

DIA director Giuseppe Governale firmly believes the men are guilty of mafia association but is frustrated that the Italian courts are finding it hard to make the charges stick.

"We find ourselves in a similar situation as those who are fighting terrorists," he says. "It's what we call asymmetrical. In other words, the adversary plays by his rules and we play by different ones. We don't have the tools to combat them."

Giuseppe Governale rejects claims there is no Nigerian mafia in Italy. He says the group's operation is much like the homegrown mafia networks. ( Foreign Correspondent: Louie Eroglu )

Mr Governale grew up in Palermo when there was a murder on the streets almost every day. For him, the fight against the mafia is personal. On the desk in his office in Rome is a picture of himself as a nine-year-old boy standing nearby the local police chief he idolised as a child. Shortly after the photo was taken, the officer and his wife were killed in a car bomb attack. It was payback from the mafia.

Mr Governale has made a career out of studying the Italian mafia's inner workings. He says the Nigerian mafia has many similarities with the old syndicate, including its "oaths, its sense of belonging, the capacity to coerce, the code of silence, the ultimate privacy pact and confidentiality."

"When you enter the organisation, you cannot get out other than by death," he says.

He has also seen how the Nigerian mafia has earnt the respect of the old mob, who he claims are "afraid that the Nigerians have the capacity to exercise the same magnitude of violence".

"Because in that world, everything is determined, not by rules but rather by who has the capacity to carry out violence. To be pitiless."

But the threat is even more difficult to contain. Penetrating their operations has been difficult for reasons of language and cultural sensitivities.

Solving the problem of Castel Volturno

Castel Volturno's citizens need rights if they are to break free of mafia exploitation, says Roberto Saviano. ( Foreign Correspondent: Louie Eroglu )

Roberto Saviano has no doubts that the Nigerian mafia is real and will remain as difficult for law enforcement agencies to root out as the Italian mob. But he says the solution lies in tackling the conditions that have made migrants vulnerable to exploitation by the ruthless crime syndicates.

"You can only resolve the problem of Castel Volturno by giving people rights," he says. "Full rights of citizenship for African workers, allowing the city to live its calling as an international city."

Vincenzo Schiavone despairs that first the Camorra, and now the Nigerian mafia, seem to have found "a perfect habitat" in the wasteland of Castel Volturno. He dreams of seeing the city rejuvenated.

"This is my territory. My mission has become to bring it back to what it once was. It's not the dream of a fantasist. The state should have done this but it has abandoned us."

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