“The boy landed in bushes and ambulance staff couldn’t find any external injuries,” said Wiener Rettung spokesman Ronald Packert.
The accident happened on Thursday morning at around 8am. The boy’s grandmother was with him in the first floor apartment but briefly left the room - which is when he climbed onto the windowsill and fell from the open window.
When she came back she saw what had happened and called an ambulance. The boy was taken to hospital with severe bruising.