“It will be the battle for Berlin,” Andrzej said, with a crooked, toothy grin. Clasping a can of beer and singing obscene anthems, he is one of the estimated 250,000 Polish supporters who will be travelling to Germany next month, with or without a ticket.

We met the 38-year-old mechanic outside the Lech Poznan Stadium before a low-key encounter with Dyskobolia, a local rival, but the talk was of war, blood and the settling of scores on an international level. Poland play Germany on June 14 and whatever the outcome on the pitch, passions will be stirred among the two largest hooligan contingents at the tournament.

To our surprise, Andrzej disappeared to the gentler side of the stadium and squeezed among the younger supporters. There were tougher fans than him at the game, who were shepherded into a huge metal cage: a couple of hundred baying skinheads. As in every Polish game, ritualised chants echoed across the stadium but there was anger too, waiting to be exported across the border to Germany. “Don’t want no education,” bellowed the crowd in a warm-up song borrowed from Pink Floyd. “Don’t want no thought control.”

Police calculate that there are between 2,000 and 2,500 potentially violent Polish hooligans. But the figure is guesswork. Each region has its own figures. There is no central list, little monitoring and no clear overview.

“Only about 5 per cent of the fan community are really hooligans,” Jaroslaw Kilinski, head of Wiara Lech, the Poznan supporters club, said. “The Germans are exaggerating the problem.”

But 5 per cent of 250,000 adds up to more than 12,000 thugs, enough to change the balance of the hooligan problem during the World Cup. By comparison, 100,000 England fans are expected, with more than 3,000 forced to stay at home under banning orders.

The dynamics of Polish hooliganism could be observed in the Poznan cage. About six organisers, none of them wearing fan regalia, slipped through the barred entrance — resembling the exercise yard of a high-security prison — and controlled the mood of the terraces. Using mobile phones to co-ordinate with other parts of the stadium, they whipped up or calmed the fans. After the match, they disappeared into the crowd.

According to Marcin Kornak, the head of the fan-monitoring agency Never Again, they were almost certainly linked to far-right groups. “The hooligan scene has become a prime penetration target for organised neo-Nazis,” he said.

The far-right group Blood and Honour has infiltrated the fan clubs of Wroclaw, Gdansk and Lodz. Each club in Poland, according to Filip Janczak, of the Poznan Supporters Association, has a hooligan cell, often just a handful of young men. “They have their own web of communication — with mobile phones and the internet,” he said.

Grudge matches bring them out. “The arithmetic is complicated,” Jacek Purski, of Never Again, said. “Legia Warsaw has 70 hardcore violent fans who can be spotted at most matches. When Legia plays away, that can swell to 400.”

Now the hooligan cells are co-ordinating their actions ready for the World Cup.

Hooligans act on unspoken rituals rather than on explicit orders: that is what makes them so difficult to monitor.

Sociologists compare the hooligan structure with the Mafia,Indeed, it is extremely violent. Six people have died in clashes between supporters of Wisla Cracow and their rival Cracovia. Training video clips on the art of kicking to cripple have been put on the internet. In lock-up garages, hooligans have gathered arsenals of axes, knives and chainsaws.

There are many border crossing points between Poland and Germany and the police know the identity of only a few offenders. Last November 100 Polish fans fought Germans in the forests of Brandenburg outside Berlin. Many were Poznan supporters and have been put on a list of undesirables. There is no sure way of stopping even these fans coming to the World Cup.

Gerd Neubeck, the deputy president of the Berlin police, calculates that many Poles will not have enough money to travel to Dortmund, in the far west, for the match against Germany. He expects that they will make the short trip to Berlin and watch it on giant screens. Trouble is likely. Among the German fans in Berlin there are at least 1,000 classified as potentially or actively violent. It could, indeed, become the Battle of Berlin.

THE NUMBERS GAME

5 million visitors expected in Germany for the World Cup next month

250,000 police on duty, including 500 foreign police officers

79 British policemen will join the contingent, including 44 in uniform

100,000 England fans are expected (3,400 hooligans subject to banning order)

250,000 to 300,000 Polish fans are expected (2,000 to 20,000 hooligans)

300,000 to 500,000 German fans planning to attend (9,500 hooligans)

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