Hundreds of refugees have started walking from Budapest to Vienna, a day after around 1,000 began a similar journey.
A Reuters witness said the group had set off from Budapest's Keleti railway station on foot to begin the 150-mile trip to the Austrian capital.
Hungary sent about 4,500 migrants to the Austrian border by bus overnight, including those who were walking on the motorway.
The first train carrying 167 migrants from Austria to Germany has arrived in Munich.
As many as 10,000 refugees are expected to arrive in the country today, police said.
German police say they are expecting up to 10,000 refugees coming from Hungary via Austria today.
Around 4,000 refugees have now reached the Austrian border after being bussed there from Hungary.
Austrian Police spokesman Helmut Marban said the final numbers "could double, if not more".
On top of 20 buses shuttling back and forth between Vienna and Hungary, a special half-hourly train service has also been put on.