Migrants are escorted by German police after they arrived by train to the main railway station in Munich, Germany.(Reuters)

© Thomson Reuters 2015

After days of smooth operation, Austria's transfer of migrants to Germany appeared to break down on Thursday as a rush of people crossing from Hungary forced it to suspend train services across that border.The number of people entering on foot in the early hours of Thursday strained resources at the frontier as the authorities scrambled to provide onward transport. Trains have also been carrying other migrants directly across the border, generally in smaller numbers."Ever more people are arriving daily," said a spokesman for the national rail company, OeBB. "It far exceeds our capacity."Tens of thousands have passed through Austria since Saturday, when it and Germanyannounced jointly that they would let a wave of migrants, many of them fleeing Syria's civil war, enter their territory.With the overwhelming majority wanting to travel through Austria to Germany, the mass transfer had gone smoothly until Thursday, when OeBB cited "massive overloading" as a reason for the suspension."That is the reason we want to slow the flow from Hungary," the OeBB spokesman said. "It is not the solution, but it would be irresponsible simply to let people keep streaming in and spend the night at train stations."Over the weekend, extra trains were provided and carriages added to existing services to handle the initial influx.Within days, however, the number of arrivals had fallen sharply, and rail capacity was reduced. That made it harder to manage Thursday's surge, which included 4,000 people who had crossed the border on foot, an Interior Ministry spokesman said.A Reuters journalist saw hundreds of people continuing to line up on Thursday afternoon at the border with Hungary, where there is no formal frontier post because both countries are members of the European Union's open-borders Schengen agreement."The suspension will definitely remain in place today, and we will have another look early tomorrow," the OeBB spokesman said. "We're assuming that the influx will remain at this high level."