In the Cosa Nostra heartland of UK Mafia boss Rancadore

Domenico Rancadore came to the UK in 1993

Clinging to the foothills of a steep-sided mountain on the outskirts of Palermo is Trabia, the quaintest of provincial fishing ports.

Outwardly it is a warm and welcoming place, popular at this time of year with the touring visitors.

But inside the walls there are watchful eyes. These are the winding narrow streets of the Cosa Nostra, and in the early 90s it was the boss Domenico Rancadore who ruled.

"He was the PE teacher," said one man we stopped. "Married to the daughter of an Italian diplomat? I think he taught locally. Nice man."

Though, of course, they know the truth. They all knew that Rancadore's day job was merely the cover. And even today, 19 years on, the Omerta - the code of silence - prevails.

But the judge who has pursued Rancadore throughout these years did agree to meet us and share what he knows. We met at a secret mountain location, guarded by armed police, at the end of a rutted and forgotten lane.

Vittorio Teresi knows Rancadore personally. They grew up together in Trabia, though the two men would take distinctly different paths.

One was destined to become the Mafia gangster, the other the anti-Mafia prosecutor.

'Come home'

"I am convinced he has information we could use, if he wants to share it," said Judge Teresi. "He was one of the top bosses at the time. He knows the secrets.

Vittorio Teresi says Rancadore was a top boss and "knows the secrets"

"The group to which he belonged was extremely tight. He was close to the leadership of the Corleonese, the godfathers, and we know he shared their strategy at that time of attacking the state directly.

"So I say to the boy I knew as 'mimmo', don't fight this extradition. Come home, come back to Italy, give some dignity to your wife and children."

When he first began his work as a prosecutor, Vittorio Teresi was still living in Trabia in his parents' villa.

His father was the doctor. They knew everyone. But soon he was forced to leave. The pressure came not from Rancadore, but from the Mafia's pervasive influence in the village.

The signals were clear. The prosecutor had to go.

When he fled to Britain, Rancadore took his wife's maiden name, and was known as Marc Skinner.

"Of course his wife Anne would know his real identity," said the judge.

"He was part of the blood family. His father, Giuseppe, was very important within the organisation. The family knew well his double activities, and Anne would certainly know his job as a teacher was merely the cover.

"She must also have known why he wanted to leave the country, why he needed to leave the family suddenly - and she must also know that he had been convicted."

Rancadore's wife Anne and daughter Daniela attended court in London last week

Their breakthrough came in 2009. Rancadore's father was gravely ill.

"We knew he might try and get in touch with the family," said Judge Teresi. "We even anticipated he might return to Italy. And we were ready.

"We stepped up our efforts and our surveillance of the family. The phone tap confirmed our suspicions. He was living in Uxbridge, on a state pension and on the money the Mafia must have been sending."

Rancadore was the boss of Trabia during the late 80s and early 90s; he ran it for a period of 10 years. There were an estimated 50 Mafiosi who would fulfil his orders. His business was extortion and racketeering.

Rancadore's group, said the prosecutor, had hijacked some lucrative public works contracts.

The low point of those years was the murders of the two anti-Mafia judges, Falcone and Borsellino, who were killed in separate bomb attacks in 1992.

In the wake of the murders, the Cosa Nostra came in for some unprecedented attention - and some of its biggest bosses were finally on the run.

Other bosses in UK?

But if the British police knew Rancadore was in the UK, then why did it take them until 2013 to arrest him?

"There are major cultural differences, different legal systems in the two countries," said Judge Teresi.

"In Britain, in fact in many other European countries too, it is hard to convey what 'a crime by association' actually means. We have tried to give more detail. We have clarified certain points. We believe there is a good case for extradition.

Tributes in Palermo to murdered anti-Mafia judge Paolo Borsellino and his guards in 1992. The killings turned up the heat on the Cosa Nostra

"These days the Mafia's money is global - it requires a global response."

A man who knows exactly how the Mafia works is Edoardo Zaffuto.

He belongs to AddioPizzo, a group that offers legal and moral support to the brave Sicilian businessmen who refuse to pay the Cosa Nostra's protection money.

"They may not have the evidence to directly link Rancadore to any murders of the time," said Mr Zaffuto.

"But if the Mafia had needed to murder someone in that district, they would have needed the permission of the boss - Rancadore. He may not have ordered the murders directly but he would have to give permission for someone to be killed."

Palermo's flying squad were not directly involved in the hunt for Rancadore, though time and again his name has cropped up in their investigations.

A sense of Omerta - or silence - prevails in much of Sicily

They take great satisfaction that another boss is in custody. They have had some big scalps in recent years, the biggest of them all the godfather Bernardo Provenzano.

Rancadore knew him, like he knows the men now running operations in Trabia. The police chief Maurizio Calvino told me that in the Mafia the blood ties are forever.

"In the Cosa Nostra the boss never loses his importance to the family," said the chief. "It's immaterial how long he has been away. In the Cosa Nostra, the past always links with the present."

If he is extradited, Rancadore will face seven years for extortion in one of Italy's hardest Mafia jails.

The prosecutor says it's hugely important Scotland Yard assisted in this arrest. They may need their assistance again.

They are suggesting Rancadore may not be the only boss who has been hiding in Britain.