Hundreds of German frontier policemen staged an extraordinary protest march yesterday against the opening up of European Union borders.

The noisy rally in the east German border town of Frankfurt an der Oder, which is within hailing distance of Poland, exposed some of the tensions in Europe before December 21 when many of the new entrants to the EU join the Schengen free travel area.

Countries joinging the agreement include the Baltic republics, Poland, Slovakia, the Czech Republic, Hungary and Slovenia, meaning that passport checks will be abolished along much of what used to be the Iron Curtain that divided communism from the West.

That should be an epochal event, but the price of uncontrolled travel from the Ukranian border to Calais is the tightening of the eastern EU frontiers, in case new waves of immigrants move westwards. And that is already causing friction across the continent.

“These countries are not yet capable of defending the EU borders,” Knut Paul, chairman of the federal police trade union, said. “We are exposing ourselves to the threat of being swamped by criminals and illegal immigrants.”

The demonstrators, many of them in uniform, marched from the Oder River bridge, which connects Germany to Poland, before attempting to barrack Wolfgang Schäuble, the German Interior Minister. Mr Schäu-ble was in the border town to discuss the implications of expanding the Schengen area with top police officials, civil servants and politicians. A cordon of police held off the protesting policemen.

Jörg Schönbohm, interior minister of Brandenburg, a region adjoining Poland, said: “What is happening is the logical result of a changing world. The action of these officers is backward-looking and hostile to Europe.”

Because the EU borders are shifting 700 kilometres (435 miles) eastward, about half the frontier police in Brandenburg face redundancy or transfer as advisers to the less hospitable Polish-Belarussian faultline.

Illegal migrants discovered deep in the Schengen area are supposed to be transferred back to their first point of entry into the EU where they can go through asylum-seeking procedures. That could give Central Europe a serious refugee problem: from Estonia to Slovenia, old barracks buildings are already filling up with Pakistanis, Chinese and Sri Lankans who were caught trying to infiltrate the EU.

The EU has been helping to modernise eastern border controls. Lorries entering its area will now be stopped mainly on the Polish-Ukranian and Slovene-Croatian crossing points, and Customs officers there have been issued with high-tech x-ray machinery and thermal imaging devices to check if people are being smuggled.

Schengen includes 13 EU member states, plus Norway and Iceland, but excludes Britain and the Irish Republic. After December 21, there will be 24 members.

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