Trains carrying hundreds of migrants started arriving in Vienna on Monday after Austrian authorities appeared to give up trying to apply European Union rules by filtering out refugees who had already claimed asylum in Hungary.
In the latest twist in a humanitarian and political crisis that is now testing the survival of both Europe's open-border regime and its asylum rules, Hungary allowed the migrants, many of them fleeing Syria's civil war, to cram into at least four trains leaving Budapest for Austria or Germany.
Many of the refugees arriving in Vienna railway station on Monday evening immediately raced to board trains heading on to Germany, as policemen looked on passively, preferring not to intervene, witnesses said.
A train also arrived in Munich from Budapest on Monday evening. German police said there were about 200 on board.
"Thank God nobody asked for a passport ... No police, no problem," said Khalil, 33, an English teacher from Kobani in Syria, as his wife held their sick baby daughter coughing and crying in her arms at the Vienna station.
He described how he and his family had been able to buy train tickets in Budapest and were headed for Hamburg, Germany, adding that he was sure of seeing a better welcome there after traipsing across the Balkans and Hungary.
"As for Germany, Syrians call (Chancellor Angela) Merkel 'Mama Merkel', he added, referring to the German leader's relatively compassionate response so far to the migrant crisis.
One of the trains was stuck for hours in searing summer heat at the Hungarian border town of Hegyeshalom, with Austrian railways citing safety concerns about overcrowding.
In line with EU rules, an Austrian police spokesman said only those who had not already requested asylum in Hungary would be allowed through - but the sheer pressure of numbers finally prevailed and, with few police officers or border officials reported in the vicinity, the train moved on, apparently with all passengers still on board.
"I CAN'T WAIT"
Ali, 34, and his three-year-old daughter Mona, were just happy to have found enough space to stand on their packed Austrian RailJet train bound for Munich.
"I can't wait," said Ali, who like many of the Syrian migrants hopes to join up with relatives already in Germany.
Children slept on the floors of carriages, exhausted. The air was thick with body odor.
The migrants' plight highlights the huge challenge facing the European Union, which has eliminated border controls between 26 states of the "Schengen area" but requires new asylum seekers to apply in the first country they enter - in this case Hungary.
Most of the migrants have no intention to stay in Hungary, even those who register there, but aim to reach richer western European countries.
The Vienna police spokesman said migrants allowed into Austria could stay for two weeks while they decide whether to seek asylum there. Those who did not would be returned to their last transit country.
Earlier refugees had expressed relief at finally being allowed to leave Budapest.
"I have been here sleeping on the floor like a dog with my two sons for six days," said Sami, a Syrian. "Today we leave this country behind and join my sisters in Munich, inshallah."
About 1,000 others waited on blankets outside the railway station hoping to follow them later. Some expressed anger at not being allowed to board trains sooner despite buying tickets.
"I bought a ticket, why did they sell me the ticket and now there's no train?" said Murhaf, 27, at Vienna station. He had paid 350 euros to be smuggled in a private car from Budapest to Vienna and had now paid 159 euros for his train ticket.
Austrian authorities have stopped hundreds of refugees and arrested five traffickers as part of a clampdown along a main motorway from Hungary against the criminal gangs exploiting the human misery following last week's gruesome discovery of 71 dead migrants in an abandoned truck near the Hungarian border.
A senior official at Austria's Interior Ministry, Konrad Kogler, denied on Monday that the clampdown, which includes increased checks on the eastern borders, amounted to a violation of the Schengen accord on free movement.
"These are not border controls," said Kogler, noting that checks were taking place across Austria's territory as well. "It is about ensuring that people are safe, that they are not dying, on the one hand, and about traffic security, on the other."
Merkel, whose country expects to receive some 800,000 migrants this year, the most of any EU country, said the migrant crisis could destroy the principle of free movement in Europe enshrined in the Schengen accord.
"If we don't succeed in fairly distributing refugees then of course the Schengen question will be on the agenda for many," she said at a news conference in Berlin.
"We stand before a huge national challenge. That will be a central challenge not only for days or months but for a long period of time."
Over the past three days, Hungarian police said they had caught 8,792 migrants crossing into the country, most of them from Serbia.
Hungary plans to tighten laws on migration this week and also plans to set up holding camps near the Serbian border. The government said it may use the army to help police protect the borders if it gets the necessary parliamentary approval.
The changes will also impose stronger penalties for the illegal crossing of borders and for damaging a 175-km fence being built at the Serbian border, and would enable Hungary to expel migrants violating the new rules.
On Monday Hungary rejected French criticism of its "scandalous" efforts to protect its border from the migrants.
Refugees who managed to board the trains heading west on Monday mixed with well-heeled business travelers and tourists, some of whom were angry over the delays to their journey.
"I have a plane to catch from Vienna Airport. I took the train because of the road checks and the traffic jam ... and now this? Are you kidding me?" said Orsolya Jakab, 35, a Hungarian accountant.