German police patrol on an empty bridge crossing the border river Inn at the German-Austrian frontier between Braunau and Simbach am Inn near Passau, Germany at dawn November 1, 2015. [Photo/Agencies]

VIENNA - Tougher German border controls have led to a huge increase in the number of migrants stuck in Austria awaiting onward travel, an allegedly confidential document from the Austrian federal government claimed.

The Kronen Zeitung reported the details of the document Monday, stating that in just 11 days, the number of migrants waiting to cross into Germany from the Austrian states of Salzburg and Upper Austria increased from 6,300 to 20,300.

The newspaper also quoted an employee of the crisis management efforts as saying emergency quarters could no longer keep up with the large numbers of migrants, and warned of a collapse of the "pass-through asylum system" that has until now been practiced in Austria.

In addition, the more hard-line the approach the German government takes, the fewer the migrants who will be allowed to travel onward to the so-called favored destination country, the source said.

The report also noted, however, that by Monday the figures had again dropped to just under 17,000, according to a federal government spokesperson who argued that the backlog of persons wishing to travel onward through Austria was being reduced.