German police said they had arrested 57,000 illegal immigrants in 2014, an increase of 75 per cent compared to 2013.

The sharp rise comes at a time when the debate on immigration is growing increasingly charged in Germany.

Neo-Nazis reportedly threatened to behead a local politician over his support for asylum-seekers this week, and a refugee shelter was torched over the weekend.

The Pegida anti-Islam movement, which dominated the politician agenda at the start of the year, has called for curbs on legal immigration.

Police said they had arrested 27,000 illegal immigrants inside Germany, and stopped another 30,000 at the borders. Most were detained at the borders with Austria and France.

“This is the highest level since reunification,” Dieter Romann, the federal police chief, told reporters yesterday.

“The number has more than tripled on the southern borders, and doubled on the western borders.” Police had also arrested 2,100 traffickers illegally smuggling people into the country, compared to 1,535 in 2013.

“Next to the international Islamist terrorism, illegal immigration is currently the biggest challenge for the federal police,” Mr Romann said.

“Our officials are working to the limit.” Germany’s federal police is a small specialised force in charge of protecting the country’s borders. General crime is dealt with by state police forces.

Large numbers of those detained were fleeing the civil war in Syria while others came from Eritrea, Afghanistan, Kosovo, Serbia and Somalia.

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Some may be genuine refugees but cannot claim asylum in Germany under EU regulations.

“Under current European rules immigration control appears increasingly difficult to me,” said Mr Romann, who has spoken out against the EU’s refugee policy in the past.

Under existing rules, refugees are supposed to claim asylum in the first member state they reach.

But Mr Romann has accused southern EU countries such as Italy of doing nothing to stop asylum-seekers using the Schengen border free area to travel on to Germany.

The rise in illegal immigrants comes against the backdrop of a similar increase in asylum applications in Germany.

There were 173,072 asylum claims in 2014, up from 109,580 in 2013.

Authorities have been struggling to provide accommodation for refugees, and the debate over immigration has grown increasingly polarised.

The Pegida movement, which has been showing small signs of resurgence in recent weeks, has accused many of those claiming asylum of being economically motivated.

Despite the vocal protests against immigrants, there has been a larger groundswell of support for them.

Pegida attracted crowds of some 25,000 at its height, while counter-protests drew more than 100,000 onto the streets.

And German churches have offered sanctuary to hundreds of asylum-seekers who would otherwise be deported.

Source: The Telegraph