The 30-year-old man and 27-year-old woman were detained at Prague airport a week ago, shortly after the arrest of a 42-year-old Iraqi suspect in Vienna.
"They were driven to the border and handed over to an Austrian escort on
Tuesday," police spokeswoman Hana Rubasova told AFP.
The pair agreed to the extradition last week after Austria issued an arrest
The three Iraqis are suspects in an attack which saw a steel rope strung
across the tracks between the southern German cities of Munich and Nuremberg, damaging the front window of a train in October last year.
A similar case occurred in December last year near Berlin when an overhead electrical line was damaged. No one was injured in either incident.
Vienna prosecutors said only a technical error prevented casualties, adding
that Arabic writings and an Islamic State (IS) flag near the crime scenes
indicated a "terrorist" motive.
The man detained in Vienna in cooperation with German police has admitted involvement in both incidents but denied any terrorist motive for the crimes, which would carry a maximum life prison sentence.
Austrian media reported that the detained Iraqi father of five was working
at a security company with access to football stadiums.
Germany is on alert following several jihadist attacks in recent years.
The most deadly was committed in 2016 by 23-year-old Tunisian Anis Amri,
who killed 12 people when he drove a truck into a Berlin Christmas market.