Thousands of asylum seekers are on the move across Europe as a result of the relaxation of internal border controls.
A new system intended to make it easier for European Union citizens to move between member countries has led to a dramatic rise in illegal immigrants.
Elena Gairabeka and her five children arrive in Austria
At the Traiskirchen refugee camp in Austria, numbers have more than doubled, from 300 to 770, since the rules were changed just before Christmas.
Many, travelling on foot, in vans and taxis, had started their journeys in the disputed Russian territory of Chechnya.
Elena Gairabeka and her five children walked across the border into Austria from the Czech Republic after initially leaving Russia and entering the EU through Poland.
The group, which included a six-month-old baby, faced night-time temperatures of minus 20C during the journey.
Mrs Gairabeka said they made the trip to join up with her husband Muslim, who had entered Austria illegally five years earlier.
Mrs Gairabeka said they arrived in Poland by train but had been unable to continue their journey until the border rules changed on December 21.
The new rules mean that staff at the internal borders can no longer check passports.
The rules do not apply to Britain and Ireland, which are not part of the so-called Schengen zone.
Last month, The Sunday Telegraph exposed lax controls on the new eastern frontier and fears that many more illegal migrants would be able to enter the EU.
"We were able to get to Poland without a visa, and we applied for asylum - that meant we could stay while the application was processed," Mrs Gairabeka said.
"Now the borders have opened I have been able to cross to Austria. We hitched a lift in a lorry part of the way and walked the rest. But I am worried they will send us back to Poland."
Most asylum seekers arriving in Traiskirchen had few possessions and little protections against the bitter cold.
But Mrs Gairabeka said it was worth the discomfort.
"To be honest, we don't care if we live here or in Poland or Britain," she said. "The main thing is that after five years we want to be a family again and my children want their father.
" Mr Gairabeka previously had to travel to Poland to meet up with his family.
Almost 2,000 soldiers still patrol Austria's borders, but they are powerless to check the passports of new arrivals.
With a border that includes the Czech Republic, Slovakia, Hungary and Slovenia, Austria has been the first to experience the wave of new arrivals.
Traiskirchen's mayor, Franz Gartner, said: "The government held parties to celebrate Schengen but never bothered to evaluate the security situation properly. If it is not going to close these borders it needs more camps."
Austria's interior minister, Guenther Platter, pledged that the new arrivals would be sent back to Poland, warning: "Anyone who comes to us from another EU country has no right to asylum here."
German police, who opposed the opening of the borders, have also reported a sharp increase in the number of illegal migrants entering the country.
Some politicians are demanding the borders once again be closed.
Harald Vilimsky, secretary-general of the Austrian Freedom Party, said there had been an "avalanche of asylum seekers", mainly from Russian-speaking countries.
Gerald Grosz, of the Alliance for the Future of Austria party, said the government was turning Austria into "an El Dorado for fake asylum applicants and criminals".