The wrecked remains of commuter train cars in Vienna.
On Monday, dozens of people were injured, including five seriously, after two trains collided head on.
The crash happened during morning rush hour in a Vienna suburb where trains going both directions use the same track.
This railway spokesperson said the crash was likely due to a technical problem, though human error had not been ruled out.
Emergency crews worked for hours to free trapped passengers and ferry the injured to hospital.
One of the train drivers was among the seriously injured.
