The brutal murder of four people at a provincial German ice cream parlour last night raised fears that the country is fast becoming a killing field for duelling mafia clans.

The attack occurred in Rüsselsheim – home to the Opel car factory – where many Italian workers have settled, establishing pizzerias and cafes with their savings. Three men, described as being of “Mediterranean appearance” approached the ice cream salon just before dusk and fired rapidly at a group of three male customers. A woman standing nearby was also killed, but it was still unclear last night whether she was a target or was gunned down by accident.

The shadow of the Calabrian mafia may thus again be stretching over the industrial heartland of Germany. A few days ago, Italian police arrested Paolo Nirta, the acting head of the San Luca clan, a stronghold of the Calabrian gangs known as the ‘Ndrangheta. Nirta is suspected of involvement in the killing of six Italians in a pizzeria in Duisburg, in western Germany, almost exactly a year ago. That was regarded as a vengeance killing: Nirta’s sister-in-law, Maria Strangio was shot down on her doorstep just before Christmas 2006.

A major man hunt was underway with helicopters and tracker dogs deployed around much of the surrounding area. The assassins were said by witnesses to have both pistols and knives.

Plainly though, the ice-cream murders may be part of an elaborate tit-for-tat. Somebody betrayed Nirta to the police last week. That usually triggers a revenge attack.

Germany was shocked by the Duisburg murders last year and it will be equally concerned by the ice cream parlour killings. There are some 540,000 Italians living in Germany, most of them well integrated. They are the descendents of “Guest workers” who were brought to Germany from poorer corners of southern Italy after World War Two to help fuel the country’s economic recovery. Until last year, there was no substantial evidence of Italian mafia involvement in the German criminal economy. The ‘Ndrangheta makes its money largely through drug trafficking, manipulating contracts in the building industry, protection rackets and prostitution. Italian involvement, even in the German drug trade, has however, been marginal.

Instead, the Calabrian gangs have used German-based Italian restaurants and suppliers as a way of laundering money. But, crime experts have been warning that this supposedly “white collar” crime would ultimately bring violence to the streets of Germany. “If we allow crime proceeds to seep into another economy, if drug or extortion money from Italy enters Germany, then that is no longer the end of the story,” says Federico Varese, a professor of criminology and expert on organised crime. “It is possible, that the ‘Ndrangheta will move up from simple money laundering to become more entrenched in the German economy – and that is the most dangerous situation you can imagine.”

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